Wouldn't it be easier to just join one flavor of fundamentalist Christian or another? A lot of them have similar views of women, aren't on the other side of an ocean, and have less of a language barrier. Especially for this guy, what with already being "deeply religious", wouldn't it have been a lot simpler for him to just join the right church and get one of the older men in the church to marry off his 7th daughter to him?
Probably, but somehow I doubt his 'religious' justification. As someone who went to Catholic school for his entire life at schools run by actually fucking Monks, the Bible is very clear that if your eye causes you to lust, put it out, and if your hand causes you to sin, cut it off. The Bible is clear you are responsible for removing yourself from Sin, not removing the Sin from the world. To attempt to judge and police the world is in fact a grave Sin because you're taking the responsibly of God in your own hands, and only God can judge the world. Man can only judge himself and police himself, everything else is God's jurisdiction.
I think the Religious thing is just his attempt to change the story to one of pity, and it fucking worked. The cops don't seen a deranged killer, they see a devout, religious young boy who was at the end of his rope and just had a bad day and got rid of sinners, and unfortunately he has to be prosecuted. I guarantee you there are pastors on Sunday who will deliver a sermon that the little shit is just a lost lamb and he was just trying to make the world a better place.
And it'll be picked up by conservative media that he's not a sexists white supremacist, he's a religious boy just killing the whores and now liberals want to police and imprison God loving Christian men, welcome to Joe's new America where you can't be white or Christian.