In his new book The Evolution of God, Robert Wright leans on the first gospel--that of Mark--to suggest that later gospels present a Jesus who is less historically authentic, but more palatable to modern tastes, especially on interfaith issues:
For many Christians, the life of Jesus signifies the birth of a new kind of God, a God of universal love. The Hebrew Bible—the “Old Testament”—chronicled a God who was sometimes belligerent (espousing the slaughter of infidels), unabashedly nationalist (pro-Israel, you might say), and often harsh toward even his most favored nation. Then Jesus came along and set a different tone. As depicted in the Gospels, Jesus exhorted followers to extend charity across ethnic bounds, as in the parable of the good Samaritan, and even to love their enemies. He told them to turn the other cheek, said the meek would inherit the Earth, and warned against self-righteousness (“let he who is without sin cast the first stone”). Even while on the cross, he found compassion for his persecutors: “Father, forgive them, for they know not what they do.”
But there’s a funny thing about these admirable utterances: none of them appears in the book of Mark, which was written before the other Gospels and which most New Testament scholars now consider the most reliable (or, as some would put it, the least unreliable) Gospel guide to Jesus’ life. The Jesus in Mark, far from calmly forgiving his killers, seems surprised by the Crucifixion and hardly sanguine about it (“My God, my God, why have you forsaken me?”). In Mark, there is no Sermon on the Mount, and so no Beatitudes, and there is no good Samaritan; Jesus’ most salient comment on ethnic relations is to compare a woman to a dog because she isn’t from Israel.
He also argues that globalization will eventually promote interfaith understanding.