Once thought up a TL for this:
POD is: Jesus meets a nice Jewish girl (let's call her Miriam), falls in love and marries her. Her father happens to be an influential rabbi, who joins the new movement. Later, Jesus will still be crucified, but that doesn't prevent an even earlier victory of Christianity: Almost all Jews convert to the new religion, and after the people of Palestine are spread over the world after an uprising against the Romans, they will start a tradition similar to the Talmudists - people will learn to read the Bible and discuss it in detail, so this Christianity will be rather pro- than anti-intellectual. And, since there are barely any Jews around, they can't blame anything on a defenseless minority, so they'll have to solve their problems in the real world. And, priests are allowed to marry (like Jesus himself), so the smartest people can procreate. Last but not least, the Christians in the diaspora didn't forget Jerusalem, and once they become powerful enough, they reconquer the area from the Muslims. Since they're way more scientifically advanced, they really manage to conquer the whole world and also administrate it so their state doesn't fall apart.
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