Belief in God is rational.
Everything has a cause. So unless there is a first cause, then you would have an infinite regress. And then nothing could exist. Therefore there must be a first cause. Therefore God, the first cause, exists. QED. (You could prove the first step a priori that everything has a cause by noting that nothing can come from nothing. This makes it a priori, not just an empirical observation).
Repentance involves the most simple level of what you are aware of and could be reasonably be expected to know better. But there is another level beyond the horizon of one's consciousness. Things that are so wrong that one is no even aware that they are wrong.