I think Christianity and religion in general is fundamentally incompatible with Noah's personality. He needs to nitpick, question, complain, and poke holes in everything. I don't think he's capable of being told something that he's supposed to literally take on faith. It's not cause he's some truth seeker searching for some greater philosophical understanding. It's because he enjoys complaining and tearing things down, and also because if he can denigrate any new belief system to the point he can safely convince himself it's bullshit, he'll feel he never has to change.