My grandfather had never been a tall man, and now he looked absurdly small, no bigger than a child. Swaddled in off-white sheets like a newborn, with just his head and the soles of his feet visible, his eyes were open and mouth disconcertingly agape, as if in surprise. His corpse was slightly raised from the floor, lain atop a rickety wooden stretcher. Beside the body, three priests in white robes intoned in Avestan, the long-dead language of the Zoroastrian scriptures, as a small fire burned in a silver urn in front of them.

It was the height of Mumbai’s monsoon season, and the air in the prayer pavilion was heavy with moisture. The occasional cloudburst outside provided no respite from heat or humidity, and the priests cooled themselves with handheld fans that resembled ping-pong bats as they repeated their sonorous chants. The funeral was the first time I had heard Zoroastrian prayers spoken out loud, though I remembered my grandfather over the years murmuring them under his breath multiple times a day, velvet cap on his head and prayer book in his hand. Besides my mother and me, the small group in attendance was mainly made up of frail friends and distant relatives, almost all of them Parsis, as the Zoroastrians of India are known.

The cremation came later the same afternoon, the heat from the chrome furnace adding to the stickiness. The body was reduced in a matter of minutes to a kilogram of ashes, which were handed to us the next morning in a knotted sack the size of a coconut. Prayers continued the next day, the extended ceremony providing a map for slowly working through the grief.

In the days after the funeral, it struck me with some sadness that my grandfather, who had spent almost a century devoted to the Zoroastrian faith, would be the final Parsi in his family line. Growing up in Britain, I’d read a bit about the history of Zoroastrianism, but only knew the basics: it was one of the oldest religions, based on the teachings of the prophet Zarathustra, who lived thousands of years ago, though nobody knew exactly where or when (Iran, central Asia, perhaps what is now southern Russia; and about 1500 BC, give or take a few centuries). The faith he preached, of an epic battle between a powerful deity and an evil spirit, in which his followers should do everything in thoughts, words and deeds to aid the side of light, was passed down orally for centuries before it was committed to parchment. It became the dominant religion of Persia for more than a millennium, until the advent of Islam in the seventh century. Some Zoroastrians who refused to convert fled, and ended up in Gujarat in western India, where they became known as Parsis after their Persian origins. They built new temples to house their sacred fires, which were tended to by priests and could never be extinguished.

The Parsis promised their Hindu hosts they would not proselytise, and over the centuries this morphed into a dogmatic aversion to conversion. The rigorous tribalism kept the small community alive and distinct for more than a millennium, but in today’s world, the same intransigence is killing it off. “You’ve seen four weddings and a funeral – well, for Parsis, it’s four funerals and a wedding,” says Jehangir Patel, who has edited the community’s monthly magazine, Parsiana, for almost 50 years. When he finally retires, he fears the magazine will simply close, as more of its readers are dying off each year. India’s Parsi population shrank from 114,000 in 1941 to 57,000 at the last census in 2011. Projections suggest that by the end of the century, there will be just 9,000 left.

My grandfather, Pestonjee Pader, was a gentle man with a raucous, childish sense of humour, but not far beneath the surface lurked a sense of tragedy. He liked to tell stories, but most of them ended in one of two ways: “… and then, unfortunately, we had to leave”, or “… and then, tragically, they passed away too soon”. Born into a Parsi family in 1922, he grew up in the Gulf city of Aden, a thriving port then under British rule, which attracted many Parsi traders. After his father died in the late 30s, my grandfather took over the family business, supplying food and other provisions to the ships that docked in Aden on their way between Europe and Asia. He also ran the Long Bar, where he watered thirsty soldiers from the British garrison. He negotiated a concession from Carlsberg, importing beer from Denmark and eventually making a handsome profit. By the mid-60s, he was on the verge of setting up an ice-cream factory, a sure money-maker in the punishing Gulf heat. But the plans fell through when revolution came to southern Yemen in 1967, driving out the British and, by extension, the Parsis, too. My grandparents escaped to Bombay, leaving all but a few suitcases of possessions behind.

For my grandfather, the real tragedies were still to come: between 1976 and 1983, he lost his wife and both his sons, leaving my mother as his only surviving child. When we flew out to visit him during school holidays in the 90s, his once-grand apartment on Mumbai’s Malabar Hill felt as if it were occupied by ghosts: a table laid with Carlsberg glasses and coasters, carefully preserved from decades earlier; photographs of the deceased on the sideboards. He padded around the too-big apartment, saying Zoroastrian prayers of remembrance for the dead several hours each day, and regularly taking the bus to the fire temple for prayers. In the evenings, he went out for dinner with his mostly Parsi friends, until they, too, started dying off. For as long as I can remember, he would say matter of factly that he was ready to die, but he kept on going, remaining healthy into his late 80s. It was only right at the end, when dementia hit, that he became weak and confused. In summer 2017, the news came that he had finally passed away, shortly after turning 95.

My grandfather stuck to his Zoroastrian faith doggedly, whatever obstacles life tossed into his path, but my mother was ejected from the Parsi fold, officially at least, when she married out. She came to London when she was 17, to go to university and then train as an English teacher. She slipped away from a planned marriage to a good Parsi boy, and later married my dad, another teacher from Southampton. Her parents, unlike many other relatives, quickly came to accept the marriage, but the strict community rules meant she was no longer a Parsi. Partly, she accepted this, and partly, she just ignored it. “No religious bigot was going to define who I was,” she told me, and she continued to feel deeply attached to the cultural aspects of being Parsi.

Although my family often visited India when I was growing up, my sister and I never learned to speak Gujarati, and there was no suggestion among our Parsi relatives that we should partake in Zoroastrian rituals and ceremonies to feel a sense of belonging to the community, or even that we would be allowed to if we wanted. This wasn’t something I fretted about. I liked the idea of a secret, Zoroastrian side of my identity, but in my studies and then my professional life, I gravitated towards Russia, not India or Zoroastrianism. On visits to Mumbai I felt like much more of an outsider than I did when walking the streets of Moscow, where I made my home as a foreign correspondent.

But the funeral stirred in me a new interest in the 3,500-year-old Zoroastrian religion and today’s tiny Parsi community. As the religion’s followers declined, why were Parsis so dogmatic about keeping their doors closed to mixed-heritage children, let alone accepting outside converts? And did this mean that the whole Parsi community was heading for the same fate as my grandfather: a drawn-out but sadly inevitable disappearance?

Nearly three years later I found a way to seek some answers: a Return to Roots trip, which took a small group of young Parsis to India for an exploration of their history and culture. The idea was loosely modelled on Birthright Israel, which brings young Jews to the Holy Land, though our version was on a much smaller scale and free of attendant geopolitics.

I landed in Mumbai one night in early March, and the next morning the group met for orientation, each of us saying a few words about ourselves and what we hoped for from the next two weeks. Five of the 15 participants were from the dwindling Parsi community of Karachi; most of the others were children of Parsi parents who had moved to North America. They were divided between those who had strong connections to the religion and those who had lost touch and wanted to re-engage with it. There was one American-Iranian, whose family came from the small community of Zoroastrians who remained behind in Iran and live there to this day. And then there was me, the only halfie.

Arzan Sam Wadia, the Mumbai-born, New York-based architect who runs Return to Roots, had told me that the tour is emphatically not meant to function as a Parsi dating service, but he added immediately that new couples had indeed formed on previous tours, which was a pleasing side-effect. Certainly, on the first morning there was a tangible feeling of excitement at the presence of so many fellow members of that endangered species, the young Parsi. One of the volunteers accompanying us, Sheherazad, a 25-year-old Zoroastrian priest, told us he would be on hand to help with logistics and answer any spiritual questions, for those who had forgotten the prayers and rituals they learned as children (and for me, who never knew them in the first place). With a crop of bleached blond hair and a mischievous smile, he was far from the humourless, conservative figure I expected of a priest. He told us to call him Sherry.

After the introductions, we headed to the Towers of Silence, a sprawling expanse of forested land in the heart of downtown Mumbai that takes its name from the stone structures inside the grounds, where the bodies of Zoroastrians are consigned after death. The whole area is closed to the public, and I felt a rush of excitement through my jetlag as our bus passed through the guarded gates, adorned with signs warning off non-Parsis. Herodotus, in the fifth century BC, wrote of Persians exposing their dead to vultures, and 2,500 years later the tradition persists: Parsi corpses are laid out inside the stone towers, also known as dakhmas (in fact, they are shaped more like amphitheatres than towers). The first dakhma was built here in 1670, when big cats roamed what was then a wild forest. Today, the grounds are populated with butterflies, parrots and peacocks, and entering the serene space from the urban cacophony outside is pleasingly jarring.

Our guide for the Mumbai leg of the tour was Khojeste Mistree, the intellectual kingpin of orthodox Parsis. Unfailingly polite yet ruthlessly dogmatic, Mistree trained as a chartered accountant before taking up Zoroastrian studies in Britain in the 60s, and later arrived back in India armed with historical knowledge to aid the conservative Parsis who wanted to keep the faith closed.

As we walked through the greenery towards one of the two dakhmas currently in use, Mistree exalted the Parsi method of consigning the dead. “It is the best and most ecologically sound way to dispose of a corpse,” he said, explaining that it prevented the earth being polluted with the evil spirits present in a dead body. Mistree told us that each dakhma could hold more than 250 bodies, laid out on slats inside the round stone structures. When the bodies have fully decomposed, corpsebearers push the skeletons into a hole in the middle, though the high walls meant none of this was visible to us.

“You’re standing here by this dakhma, and what can you smell?” asked Mistree in his distinctive voice, which drops just a hint of Bombay twang into the soaring cadences of an Oxford don. “That’s right. Nothing. Whatever scurrilous gossip you read in the papers about rotting corpses and so on, it’s nonsense.”

As recently as the 80s, hungry vultures had swooped into the dakhmas and picked Parsi corpses clean in a matter of days. Then, in the space of a decade, the birds died out, mainly owing to the use of diclofenac, a drug fed to livestock that poisoned vultures when they fed on the carcasses. Bodies inside the dakhmas were instead left to decompose naturally, which could take several months. On certain days, people living nearby could catch a putrid whiff of decaying human flesh from their windows. In 2006, someone sneaked a camera inside one of the dakhmas and leaked photographs of the gruesome sight online. Even the staunchest advocates of dakhma consignment were horrified, and began thinking up possible solutions. A programme to breed new vultures came to nothing. There was brief excitement at the creation of a specially designed mixture of herbs and chemicals, stuffed into the orifices of the dead, but it was so effective that the dakhma floors became covered in a layer of human slurry, on which the corpsebearers kept slipping, making their unenviable job still more difficult.

Eventually, angled solar reflection panels were installed at the top of the dakhmas to speed up the decomposition process, but a small group of Parsi reformists believed a more dignified option should be available. They raised money for a funeral hall, which was opened in the suburb of Worli in 2015, and that was where my grandfather chose to be cremated two years later. A little over 10% of the Mumbai Parsi community now opts for this method, mainly those who want to ensure that relatives who have married outside the faith will be able to attend their funerals. The priest who presided over my grandfather’s funeral was one of two who agreed to work at the new prayer hall. The conservative majority was furious, and banned them from performing ceremonies at the Towers of Silence.

“I’m sorry to say,” said Mistree, in a tone that was notably unapologetic, “that those Parsis who opt for cremation will go to hell.” Later, he clarified that Parsis who lived abroad could choose alternative methods, though never cremation, as it sullied fire with the evil spirits present in a dead body. But for those who lived in Mumbai, like my grandfather, there was no excuse. In Mistree’s severe reading of Zoroastrianism, a man who had spent most of his 95 years on Earth steeped in prayer, and abiding by the exhortation to good thoughts, words and deeds, had been despatched to hell.

The next day, we boarded an open-top double-decker bus for a tour of the religious sites and cultural monuments of Parsi Mumbai, and a lesson about the Parsi influence on India’s history. Mahatma Gandhi’s intellectual mentors? Parsis. Biggest philanthropists of 19th-century India? Parsis. The first underground cinema carpark in India? Built by a Parsi. “It is quite mind-blowing how so few people have given so much,” said Mistree over a microphone, as our bus weaved through the jostle of the streets, above the honking cars and the chink-chink of the machines making juice from sugar cane. We lunched at the Ripon Club, a Parsi dining venue opened in 1884, amid grand portraits and busts of illustrious past members and tables seating a few geriatric current ones.

The following morning, in a lecture at Mistree’s apartment, he laid out the basic tenets of Zoroastrianism. I was impressed with its answer to the agnostic’s most vexing question: why, if there is an almighty God, is there so much suffering on earth? The Zoroastrian God, Ahura Mazda, is locked in a permanent battle with Ahriman, an evil spirit. Ahura Mazda is omniscient but not omnipotent, meaning that famine, disease, killings and other evils are not the work of a jealous and vengeful God, but are instead the temporary triumph of Ahriman. Early Zoroastrianism had a great influence on other major religions, and some scholars believe that Jewish eschatology grew out of Zoroastrian thinking. The three wise men of the nativity story are thought to have been Zoroastrian priests.

Mistree moved on to the holy fires, which are central to Zoroastrian worship. Creating the “highest grade” of fire requires the merging of 16 separate fires, he told us, including fire from a lightning strike and fire from the house of a king. The resultant super-fire takes 14,000 hours of prayer to consecrate, and can subsequently only be fed with sandalwood. “I was in England when Coventry cathedral was consecrated and the ceremony was only six to eight hours,” he said, pausing for us to savour the comparison. Mistree also spoke of the importance of the sudreh and kusti, an undershirt and belt tied ceremonially while praying, which had to be worn for any visit to a temple. Mistree insisted that to be a “real” Zoroastrian, a person had to wear their sudreh and kusti every day. Because I hadn’t had a navjote – the Zoroastrian coming of age ceremony – I was not eligible to wear them, and thus not permitted to enter any fire temples. (Since a still-contested reform a century ago, children of mixed marriages in which the father is the Parsi can have a navjote and join the fold, but if the mother marries out, it’s game over.)

Beneath the zealous adherence to ritual was a basic theology that seemed both simple and admirable. Zoroastrianism does not prize concepts such as guilt, martyrdom or asceticism. There is, instead, an obligation to work hard, make money, enjoy the proceeds and give generously. “Fasting is a sin. Being unproductive is a sin,” said Mistree. “To be spiritual you have to purposefully generate wealth, do it honestly and then share it.”

The exhortation to make money perhaps helps explain why many Parsis have been so successful in the world of business. My grandfather would speak about the work of lawyers and accountants with a note of wonder in his voice that some might reserve for spectacular works of art. “He is good with money” was perhaps his ultimate compliment. The most famous of the historical Parsi entrepreneurs was Jamsetji Tata, who was born into a poor family of Parsi priests in Gujarat in 1839, made his first money in the opium trade, and eventually became one of the 19th century’s most prominent industrialists and philanthropists. His holdings went on to become Tata Group, which today is one of the world’s largest companies.

Our tour group was granted an audience with Jamsetji’s 82-year-old great-grandson Ratan Tata, who spent more than two decades as chair of the group and still runs its charitable trusts. One afternoon, we drove to an office block in Mumbai’s business district and filed into a meeting room inside. Tata entered soon after, stooped and hesitant, his wavy grey hair in a side parting. Sitting below a portrait of his ancestors, he spoke to us for an hour. He was delighted that we were taking an interest in our Zoroastrian roots, and described his vision of a typical Parsi as “happy and joyful rather than revengeful and destructive”. Yet Tata seemed to have a pall of sadness over him, I thought, as he reflected on his own history as part of the community. When an earnest member of our group asked him to recount a time when his faith had positively influenced his life, he spoke instead of his escape from his overbearing Parsi family to the US, where he was able to study architecture and finally felt free and happy, before he was dragged back to India to be installed in the family business.

The evening before, we had paid a house call on Jimmy Mistry, a Parsi hotelier and bon vivant whose exuberance could hardly be more at odds with Tata’s melancholy, understated vibe. Mistry had built himself an ostentatious tower block in the suburb of Dadar, and had decorated its soaring exterior with oversized motifs of winged lions and bearded warriors, in homage to the grand ruins of Persepolis in Iran, the ceremonial capital of the Achaemenid empire, whose dominant religion was Zoroastrianism. On the ground floor of Mistry’s block, there was a newly built fire temple, where our group stopped for a prayer. As this was a private temple, the fire had not been consecrated and so it was a rare case when, as a non-Parsi, I was allowed to enter. But as I went to fix a head-covering, copying the others in the group, Sherry, our young priest companion, accosted me. “It’s better if you wait outside,” he said firmly. I sat alone in a wicker chair, listening to the lilting intonations of the priest waft from the temple without being able to see a thing.

After the half-hour of prayer, we ascended in a lift and emerged into a dining room on the 19th floor, where a glass sculpture of a horse was suspended from the ceiling. A husky wearing a jewelled cravat padded across the chequered marble floor to greet us, and then came the host, wearing a tight black T-shirt and Louis Vuitton loafers. “Welcome to my humble abode,” Mistry said with a grin. We stepped on to a roof terrace just in time for the hazy sunset, and were then ushered up a floor to yet another terrace, where we chatted with Mistry and his family over canapes. It was a disgrace, he said, that there were so many rich Parsi businessmen who were not following the Zoroastrian command to spread their wealth. “Enough of silent charity, tell us what the fuck you’ve done for the community! We need to start shaming people,” he said. I asked him how money could help reverse the decline in the Parsi population. What about taking a more inclusive line on who can be a Parsi? “Patrilineality is the only thing that has saved us over the centuries and allowed us to keep our identity,” he said, as the city darkened below.

Our programme in Mumbai came to an end, and we left early in the morning for the hill station of Lonavala. Mistry had organised a team-building exercise for us at a retreat he owned, where corporate executives receive military-style counter-terrorism training. After a bumpy hour in a jeep and then a short boat ride, we arrived at the luxury bootcamp, where the rooms had Kalashnikov lamp-stands and hand-grenade door handles, as well as Mistryisms engraved into various fixtures. “‘A gun is like a woman: it’s all about how you hold her’ – Jimmy Mistry” was etched into my bedside table. As the sun set, we were told to stand to attention as the national anthem played, and then the staff handed out fatigues to change into for the exercises, which I decided to skip, feeling a little queasy at the militarism. A billboard informed guests that the complex had been set up to help Indians take revenge for the 2008 Mumbai terror attacks, in which Pakistani gunmen killed more than 150 people.

This kind of patriotism has helped the Parsis to remain unscathed as India’s turn towards Hindu extremism intensifies under prime minister Narendra Modi. “Their love is without condition, without any expectation, and therefore the purest possible,” Modi said back in 2011, when he was still chief minister of Gujarat, suggesting that the Parsis were a model minority that others would do well to follow. Money has also helped: the Tata group has been the most lavish donor to Modi’s BJP party in recent years, with one of the Tata trusts giving 3.6bn rupees (£36.2m) in the 2018-19 financial year. The Parsis have long prided themselves on being able to get along with the rulers of the day, whoever they may be, and even the Parsi origin story reflects this knack for astute political messaging. When the refugees from Persia landed, so the tale goes, the Hindu king of Gujarat produced a full glass of milk, to signal that there was no space for new arrivals. The Persians stirred a spoonful of sugar into the milk without spilling any, to show they would sweeten the kingdom without disturbing it.

For the second half of our tour, we journeyed north to Gujarat. One of our first stops was Sanjan, the port where our ancestors arrived more than 1,000 years ago. A hot wind buffeted us as Sherry led a brief prayer on the sandy banks of the Varoli river, at the spot where the arriving Persians may or may not have produced that spoonful of sugar, and then we continued further north.

There was an energy and excitement inside our tour bus during the long journeys of the next few days, despite the unavoidable theme of ageing and decay that marked much of the trip. We played raucous games of Mafia and danced in the aisle to songs blasted through a bluetooth speaker. Sherry was a ringleader in both the card games and the dancing, rallying the troops and wiggling his hips to the music. A popular choice was Bohemian Rhapsody, sung by the most famous Parsi of them all, Farrokh Bulsara. Born to Parsi parents from Gujarat who resettled in Zanzibar for business, Bulsara went to school near Mumbai, moved to Britain in 1964 and soon took the name Freddie Mercury. He was quietly ignored by much of the community owing to his life choices and sexuality – I remember once perusing a book of 100 Famous Parsis at a relative’s house and finding multiple bridge construction engineers, but no Freddie Mercury – but the young diaspora Parsis on the bus had no qualms in claiming him as one of their own.

I started to ponder the idea of having a late-in-life navjote, egged on by many of the friendly co-participants in the tour, who thought it would be a fun excuse to all meet up again. I floated the idea with Sherry, but as we got chatting on the bus, I quickly realised I had been mistaken to infer from his bleached hair and carefree demeanour that he was a reformer and would approve of the idea. In Zoroastrianism, there is no need to be ascetic or severe in order to be conservative. Sherry told me that if either parent was not a Parsi, the child was not one either, and he would not perform a navjote. He did not even accept the century-old ruling allowing navjotes for those children who have just a Parsi father. It seemed odd, given that Sherry was clearly devoted to the community’s survival, and spoke with visible passion about his work as a priest. Wasn’t this kind of attitude hastening its decline? “We want to focus on quality, not just quantity,” he said.

I pointed out to him that there were many people on our tour who might end up marrying non-Parsis. Was it really necessary to kick them and their offspring out of the religion? “They know what they’re getting into,” he said, in a tone that brooked no further discussion. Sherry combined a fervent commitment to religious dogma and ritual with a remarkably warm, laid-back attitude to just about every other aspect of life. It was a curious combination, but one I came to recognise in many Parsis we met.

We arrived late one evening in Udvada, the small Gujarat town that houses the holiest fire in all Zoroastrianism, the Iranshah. Laying eyes on the Iranshah was set to be the highlight of the tour for most of the group. If legend is to be believed, the fire was consecrated shortly after the arrival of the Parsis in India, and has been burning constantly for more than a millennium. The current temple that houses it dates from the 1740s, and before priests are allowed to conduct prayer ceremonies there, they must undergo a nine-day purification ritual, during which they can have no human contact. The narrow lanes that make up the centre of old Udvada are lined with once-spectacular Parsi mansions now mostly fallen into disrepair. Just a handful of Parsi families still live in the town, though there are a number of inns for the pilgrims who come regularly from Mumbai and across the world. We checked into one of them, which had simple rooms that were bare save for a bed, a ceiling fan and a small representation of Zarathustra on the wall.

The next day, while everyone else went to take the requisite pre-prayer shower, I paid a visit to Khurshed Dastoor, the Iranshah’s high priest. He lived across from the temple, in a villa with windows open to the street, through which he was visible sitting at a desk, dressed in white. Dastoor beckoned me into his home with a flick of the wrist. He had a week of beard, and meaty earlobes that reminded me of my grandfather’s. Now 57, he had undergone priestly training at the same time as studying business and economics in Mumbai. On the wall were portraits of his father, grandfather and great-grandfather, and he could trace his lineage back 21 generations, all of them high priests of the Iranshah fire. He took up the role in 2002, when his father died. “Sometimes I thought I didn’t want to do it, but then I realised I had no choice. I think if you are born into this kind of family, you’re stamped that you will become a priest,” he said, brushing away persistent mosquitoes as he spoke.

Dastoor told me that nowhere in the Zoroastrian texts does it say children from mixed families should not be allowed to be Zoroastrians. When I asked him about Mistree’s assertion that people like my grandfather who chose to be cremated would go to hell, he became irate. “This is where we’ve gone wrong as a religion,” he said. He told me that while he would personally prefer to be consigned to a dakhma, adherence to ritual and dogma was a secondary concern: “The improvement of your soul, ideas, the kindness you show to people, to help educate and show charity to your family, your whole community and all of society – this is how we should measure a good Zoroastrian.”

I was pleasantly surprised to find that one of the religion’s highest priests was a reformer. I asked him whether, if I did decide to have a navjote from a liberal priest, I would be allowed into his temple to see the Iranshah fire. He shook his head, with perhaps a hint of regret. He was bound by the regulations of the town’s nine-priest council, and while he was open to discussing all kinds of reform, the votes were always eight to one against him. Even his mild utterances in favour of change had got him “in a soup” with traditionalists, he said.

Still, he was adamant that the community would need to make serious changes if it was going to survive. But what, exactly? He sighed. “If I said conversion, I would be torn down. It’s not the right time and not the right place. But we have to think of something. Though, to be honest, I doubt we can make a difference. I don’t see any optimistic future.”

There was something inspiring about the people we had met who were upholding a tradition that went back more than three millennia. I felt proud of my connection to this heritage, and a little deflated that I could never become a “real” Parsi. Still, it was hardly devastating for someone who had not previously felt a strong connection to the community. I was more interested how some of the others on the trip felt, especially the women. They had grown up practising the religion, had been interested enough to come on this trip, and were being told they would be kicked out if they married out. Many said they would prefer to marry a Parsi, but most accepted this was unlikely, given how few they met in their normal lives. Our tour had not, as far as my sleuthing could detect, resulted in the formation of any new Zoroastrian couples.

“It’s very sad, but it’s only in India,” said Tanya, a 28-year-old film-maker, born in Karachi and raised in Toronto, on being told she was no longer a Parsi if she married out. While she was proud of both her Zoroastrian faith and her Parsi heritage, she thought it absurd to insist that the Parsis should be the religion’s only gatekeepers. In the diaspora communities of North America, fire temples are open to everyone, and there is no controversy over navjotes for children of mixed parentage, she told me. The small community of Iranian Zoroastrians is even more liberal, allowing female priests, and there are also nascent neo-Zoroastrian movements in parts of the Middle East. “Zoroastrianism will always be there, it doesn’t need a race to exist,” she said. “I’d rather the religion flourishes and moves on and affects people positively than it’s a secret club you are born into.”

As the tour approached its end, we visited Navsari, the city from which the Tata family originated, and where both of my Parsi great-grandmothers were born and raised. We stopped at a library that housed ancient Persian and Gujarati Zoroastrian texts, the grand reading room adorned with portraits of illustrious Parsis of yore. We also stopped at the Vadi Daremeher, a seminary that has trained Parsi priests for nearly nine centuries, but no longer has any students.

On my last day before leaving India, I met with the Parsi leader Dinshaw Tamboly, who has long been an outspoken reformist voice, and was the driving force behind the creation of the prayer hall and crematorium where my grandfather’s funeral had taken place. He wanted to be cremated when he died, he told me, and was adamant that new voices would win out over traditionalists in the end. As we spoke, his phone flickered into life with an urgent message. An elderly priest in Mumbai had accidentally set himself on fire while praying in his fire temple, and died.

The news made me think about two elderly priests I had met a couple of days earlier, when we hopped off the bus at Nargol, a coastal town where the formerly sizeable Parsi population has dwindled to just a few families. Darabshaw Govadia was 86 and could barely walk; he was helped by his brother Rusi, a former bus driver who, at 80, was marginally sprightlier. Both priests were living inside the local temple, a handsome yellow structure with a sloping roof and fringed with lush greenery. They tended the fire throughout the day and night, always wearing their billowing white robes and receiving their meals from the town in tiffin boxes. They told me they had just a few visitors each day.

I asked who would replace them when they were no longer physically able to perform their duties. “We don’t know,” said Darabshaw in a croaky whisper. We concluded our stilted chat as the rest of the group emerged from saying their prayers, and we all assembled around the brothers on the steps of the temple for a group photograph. Then, it was time for us to leave. The two brothers smiled faintly in farewell, and shuffled back into the temple, to resume the prayers at their sacred flame.

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