Reading the letter, certain details sound untrue. Gibson is pretty serious about his fundie kind of religion and I don’t expect him to say that the Torah (i.e. Pentateuch) contains a mention of ritual sacrifice of Christian babies, both because the Torah cannot mention Christians and because Gibson of course thinks that the Torah is inspired by his god. So while other accusations sound like what Mel would say, I have to doubt the letter as a whole, since Eszterhas doesn’t sound like a reliable source. This, of course, doesn’t absolve Gibson of older antisemitic statements.