You probably know the game of telephone: a sentence whispered down a line of children arrives at the end as something gloriously wrong. Now imagine the line stretches from northern India to medieval France, takes the better part of a thousand years, and passes through half a dozen religions. That is roughly what happened to the life story of the Buddha.

By the thirteenth century, Christians across Europe were reading, preaching about, and praying to Saint Josaphat, a pious Indian prince who abandoned his father's palace to seek God. He had a feast day in church calendars. Nobody had the faintest idea he was the Buddha. His journey shows how ideas travel, and what they keep when they arrive.

The traditional story goes like this. Prince Siddhartha Gautama is born into luxury. His father has been warned by a prophecy that the boy might become a great holy man instead of a great king, so he keeps his son sealed inside the palace walls. No sick people, no old people, no funerals. Just gardens, music, and a very carefully curated feed.

Inevitably, the prince slips out. On successive trips he sees an old man, a sick man, and a corpse, and finally a wandering ascetic who seems strangely at peace. Shaken, he leaves behind his palace, his wife, and his newborn son to search for a way out of suffering. Works like the Lalitavistara and the poet Ashvaghosha's Buddhacarita, composed in the early centuries CE, polished this into one of the great narratives of Indian literature.

What makes the story so portable is that its core insight doesn't depend on Buddhist doctrine. Comfort hides suffering. The protected life is an illusion. Wisdom begins when you finally see what you were shielded from. A Manichaean, a Muslim, or a Christian monk could read it and nod along. Each faith offered a very different cure. The diagnosis, it turned out, was almost universal.

Takeaway

The ideas that travel furthest are often not the ones with the cleverest answers, but the ones that ask the most universal question. A shared diagnosis can cross borders that competing cures cannot.

The first major stop was Central Asia. There the Manichaeans, followers of the third-century Persian prophet Mani, who cheerfully borrowed from Buddhism, Zoroastrianism, and Christianity alike, retold the tale. Fragments found at Turfan, a Silk Road oasis, show the Bodhisattva already becoming a figure called something like Bodisav. From there the story reached Baghdad, where by around the eighth or ninth century an Arabic version circulated: the Kitab Bilawhar wa Budhasaf, a book of moral wisdom framed as conversations between a sage and a prince.

Then came a tiny accident with enormous consequences. In Arabic script, the letters for 'b' and 'y' differ only in the dots beneath them. A copyist's slip turned Budhasaf into Yudasaf. When Georgian Christian monks adapted the story, the prince became Iodasaph, converted by a hermit named Balahvar. The Greek version, long credited to John of Damascus but probably the work of the Georgian monk Euthymius on Mount Athos, made him Ioasaph. Latin rendered him Josaphat, conveniently echoing a biblical king.

Each culture kept the frame and swapped the furniture. Enlightenment became baptism; the Buddhist teacher became a Christian hermit armed with parables. Nobody was trying to deceive anyone. They were simply doing what storytellers have always done.

Takeaway

Transmission is never neutral: every culture that passes an idea along leaves its fingerprints on it. Sometimes the smudges become the most permanent part.

For centuries, Barlaam and Josaphat flourished in Christendom. Their story appeared in the Golden Legend, Jacobus de Voragine's thirteenth-century bestseller of saints' lives, and was translated into everything from Old French to Old Norse. One of its parables, about choosing between caskets, eventually echoed through to Shakespeare's Merchant of Venice. The two saints even entered the Roman Martyrology, with a feast day on November 27.

There were hints along the way. Marco Polo, describing the Buddha's life as he heard it in Ceylon, remarked that had the prince been a Christian, he would have been a great saint, which is a delicious piece of accidental irony. The Portuguese historian Diogo do Couto spotted the resemblance in the sixteenth century. But the connection was only firmly established around 1860, when scholars such as Édouard Laboulaye and Felix Liebrecht compared newly available Buddhist texts with the Christian legend and found the match unmistakable.

The episode is a little embarrassing and a lot illuminating. It suggests religions are less like sealed containers and more like busy marketplaces, trading stories and moral intuitions across borders their followers barely knew existed.

Takeaway

Religious traditions often present themselves as self-contained, but their stories reveal a messier, more connected past. Recognising borrowed material doesn't diminish a tradition; it shows how deeply humans share certain concerns.

Today we argue about cultural appropriation, interfaith dialogue, and whether all religions share a common core. Saint Josaphat complicates every tidy position. Borrowing certainly happened, but mostly through honest misunderstanding. Shared values were real, yet each faith remade the hero in its own image.

Perhaps the lesson is that ideas are never owned outright. They wander, change shape, and pick up new names along the road. The prince who left his palace, it seems, never stopped travelling.