Too much of religious identity depends on thinking that Jesus was not good. However there are issues which are legitimate. Already pointed out by Saadia Gaon. The most obvious issue is that Jesus does not equal God. And that should be obvious just by reading the NT itself.
But forgotten in this discussion is always the approach of "Emanation" [Atzilut] -Emanation of the Divine light to create lower worlds is very well accepted in all medieval mystics. So souls that come from Emanation are thought to be "divine" in that they contain the Divine light --with no division between them and God.
[And that is the major character of Atzilut/Emanation].
So being in particular always against Jesus as a general rule has just become too much embedded in one's very identity.
So what I suggest is that religious identity ought to be based on belief in God and the law of Moses, not being against Jesus. I mean to say that religious identity is important, but it ought to be based on true facts
Being against gentiles also seems to be too much of the identity of religious people. Besides that i have noticed a lot of the statement of the Talmud, "All who insult, insult with their own deficiency."Also I might mention that there is way too much nationalism that is mixed in with religious identity. Rav Elchanan Wasserman thought and wrote that this came from the 1848 revolutions, but I noticed that national identity and that it is connected with the soil seems to stem from Simon DeMontfort: England for the English”. By that approach he was able to unite the lords against Henry III and in fact create the structure of limited government, but i think that one ought to be devoted to keeping and learning Torah. I do not think national identity should have anything to do with that.
I might mention that I noticed a lot of nationalism when I read about Sparta and Athens in the history of the war between them. But I did not see that it was tied to the land specifically,, and in terms of the actual issue I think reading Howard Bloom's Lucifer Principle opened my eyes to the issue and also reading Hegel
