Sensationalism sells, but is nearly never faithful to the facts.
Christianity reached Asia, the Assyrian Church's missionary work brought Christianity into central Asia and into China, as the Xi'an Stele and Jingjiao Documents demonstrate.
St. Thomas missionary journey to India is, from best I've been able to gather over the years, one of the more credible apostolic journeys we have (in terms of extra-biblical accounts). The ancient presence of the Mar Thoma Christians of India is solid. There was a Jewish community where Thomas is said to have gone, going to India would certainly have been a long--but hardly unlikely--task. There was ancient trade networks between the Roman Empire and ancient China. India was well known in the ancient Greco-Roman world.
Christianity moved east very early on, among the Parthians (later Sassanians) of Persia, into Bactria, and into India. So St. Thomas could have reached India through those ancient trade roads, and other Christian missions continued and helped solidify a number of important eastern centers of Christianity, such as Edessa in Mesopotamia.
There's simply nothing but a sensationalist story rooted in a Western romantic and mystical fascination with an "exotic" "Orient" that was common in the 19th and early 20th century going on with a supposed visit of Jesus to Tibet/India.
But the presence of Christian missions to India, going perhaps as far back as St. Thomas the Apostle, are credible. Though much less sensational.
-CryptoLutheran
