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).
q94 A song of thanks to the God of Israel. q98e45e46e47e48e51e55 [edited. e55 is my attempt at 6/8 time] q96 e files are from about ten years ago. q files are more recent. There were lots of other files but a good deal was lost.