I am inclined to see the question of religious belief as a judgment call. If we are looking for proof of the sort we have for the claim that the earth goes around the sun, then this isn't going to work. But there are facts and evidence that seem to be relevant here. There are reasons that can be given on both sides. Because a lot in our lives depend on how we decide, we have to "call it" one way or the other. (Do we go to church or not? Do we follow a religion? Do we use any religious texts as a guide for life? etc.)
Consider the question of whether someone loves you enough to get married to them. Can you prove that that person will be a good husband or wife? If you wait for proof in some strict sense, then no one will get married. But you can see evidence of someone's love, or more seriously, evidence that someone's love is deficient. Or you could ignore it. People get married to abusers. They should have seen that something was wrong, but they closed their eyes. That may have seemed like true faith to them, but it seems like a recipe for unhappiness now.