I am an ordained Buddhist priest and I want that known right from the start before I share my thoughts.
1. I absolutely do not believe any of those old Russian hoaxes about Jesus having been in India. There is absolutely no real evidence for such a claim. Even if someone named "Yeshua" had been in India that is no big deal as it was a common name and there was trade between India and the Roman Empire at that time. So would it have been possible? Sure. Likely? No, not if Jesus was in fact merely the son of a carpenter and not of, say, a merchant or a scribe.
2. There is absolutely no reason to try to derive Jesus teachings from Buddhism. A near contemporary of Jesus, Hillel, also taught about a loving God and about mercy and compassion and no one ever ties to claim he went to India. The fact is that just about everything Jesus taught has precedents for it in the Hebrew Scriptures and in the religious and spiritual climate of 1st century CE Israel. You don't need to be Indian or Buddhist to have an insight into the true nature of reality or to realize that love and compassion is perhaps better than vengeance and feuding, and that if there is a God it is better to relate to God or Ultimate Reality as a loving presence, like a father (Jesus used the word "abba" or "daddy") rather than as some kind of petty dictator (or even a Roman Emperor). Read some of Shelby Spong's books about Jesus and you will see how Jesus was in fact very much a Jewish sage.
3. Even from the Buddhist side there is the teaching that there are pratyekabuddhas (solitary buddhas) who awaken to the truth in lands and times where there is no Buddha Dharma. Or from the Mahayana point of view the bodhisattvas can appear anywhere, even in lands and times where there is no Buddha Dharma. They do not teach the four noble truths or dependent origination, but they do demonstrate kindness and compassion, generosity and detachment, in a skillful way that accords with the culture of the land and time they appear in, but they are not self-consciously Buddhists.
4. There are parables of Jesus that sound similar to Buddhist parables. This may be just coincidence, and in fact the parables do have significant differences in detail and even overall intent. It may also be that certain stories traveled the trade routes from China to India to the Roman Empire and teachers and storytellers in all lands drew upon this common stock of stories. I think that is very possible. As an example, compare the parable of the prodigal son in the Bible with the story of prodigal son in the Lotus Sutra and you will see the similarity but also the differences.
5. People do not give Judaism enough credit. They read the wrathful God portions of the Hebrew Scriptures but never seem to pay much attention to the parts that Jesus himself honed in on - esp. the more universalizing and justice centered teachings of the prophets like Isaiah. Catholic and Orthodox Bibles also contain books like The Book of WIsdom and Ecclesiasticus which shows the direction Judaism was moving during the times of Hellenization and the Roman occupation. Judaism was transforming from a tribal law code or the religion of a small kingdom into a more cosmopolitan wisdom tradition (though that is oversimplifying a bit perhaps), and this especially true of the rabbinical Judaism that developed after the destruction of the Temple in Jerusalem by the Romand in 70 CE. In fact, I think it is kind of anti-Semitic to constantly claim that Jesus was more of a Buddhist rather than a Jewish sage of his time.
Would I like to be able to claim Jesus as a crypto-Buddhist? Sure I would, but I think that it is a completely irresponsible and unnecessary move to make. I think there is no evidence for it, it overlooks the actual sources in the Jewish tradition and culture of the time, and I suspect anti-Semitic motivations for the original hoaxes. I think such a claim, in the end, does a disservice to both Jesus and to Buddhism and glosses over some pretty significant differences, whereas the similarities can be accounted for by a common human nature that is at heart insightful and compassionate.
Namu Myoho Renge Kyo,
Ryuei