You can't stress the importance of something you don't believe in. He doesn't believe in there being any sort of objective morality. He believes that it is up to a person themselves to define what is morally right and wrong, with empathy being an important guiding factor in preventing bad things from being done.I'm pretty sure TJ is going to go to hell, not for not believing in God, but generally for being a fucked up person and not having any redeemable traits at all. You'd think he'd stress the importance of morality in general and understand some of the fallacious things surrounding the relationship between morality and religion, but no, not really.
The problem with that though is that TJ has no concept of empathy himself. He's struggled with placing himself in other peoples shoes or understanding why people might care about something. Unless it effects him personally, he doesn't seem to care at all. The DaddyOFive drama was a perfect example of this.