June Singer, on the psychiatrist Carl Jung’s view on the psychology of religion, from her book Boundaries Of The Soul:

In a filmed interview Jung was asked, “Do you believe in God?” He replied with an enigmatic smile, “I know. I don’t need to believe. I know.” Wherever the film has been shown an urgent debate inevitably follows as to what he meant by that statement. It seems to me that believing means to have a firm conviction about something that may or may not be debatable. It is an act of faith, that is, it requires some effort. Perhaps there is even the implication that faith is required because that which is believed in seems so preposterous. On the other hand, it is not necessary to acquire a conviction about something if you have experienced it. I do not believe I have just eaten dinner. If I have had the experience, I know it. And so with recognizing the difference between religious belief and religious experience. Whoever has experienced the divine presence has passed beyond the requirement of faith, and also of reason. Reasoning is a process of approximating truth. It leads to knowledge. But knowing is a direct recognition of truth, and it leads to wisdom.