Einstein rejected all fear based and moral religion. The only valid aspect of religion for him lay in the third kind of religion; cosmic religion and he attempted to describe this cosmic religious feeling in this article, which he said had been a part of religion at all periods of history, although it was rarely found in a pure form: It is difficult to elucidate this feeling to anyone who is entirely without it, especially as there is no anthropomorphic conception of God corresponding to it. The individual feels the futility of human desires and aims and the sublimity and marvelous order, which reveal them both in nature and in the world of thought. Individual existence impresses him as a sort of prison and he wants to experience the universe as a single significant whole. The beginning of a cosmic religious feeling already appear at an early stage of development, e.g., in many of the Psalms of David and the Prophets. Buddhism…contains a much stronger element of this. The religious geniuses of all ages have been distinguished by this kind of religious feeling, which knows no dogma and no God conceived in man’s image; so that there can be no church whose central teachings are based on it. Hence it is precisely among the heretics of every age that we find men who were filled with this highest kind of religious feeling and were in many cases regarded by their contemporaries as atheists, sometimes also as saints. Looked at in this light, men like Democritus, Francis of Assisi, and Spinoza are closely akin to one another. How can cosmic religious feeling be communicated from one person to another, if it can give rise to no definite notion of God and no theology? In my view, it is the most important function of art and science to awaken this feeling and keep it alive in those who are receptive to it.
Paul Tillich preferred to use a slightly different terminology for referring to what Einstein called “cosmic religious feeling,” but he was talking about the same kind of experience. In his Systematic Theology, for example, he stressed the importance of the awareness of the infinite. It arose, he said, from our human recognition of our own finitude, which simultaneously disclosed, that which was not finite. This was an integral and necessary part of the existentialist base that lay under much of his philosophical system. Tillich also explained how important the idea of the holy was in his theology. When he was a child he lived in Schonfliess that was still surrounded by its medieval wall and towered gates, and governed from the old medieval Rathaus or town hall. He remembered how they lived in the Parish house…with a confessional Lutheran school on the one side and on the other a beautiful Gothic church in which Father was a successful pastor. It is the experience of the “holy” which was given to me at that time as an indestructible good and as the foundation of all my religious and theological work. He knew at first hand what it was like to live with the sacred presence of the numinous surrounding him on all sides, which enabled him to understand the enormous importance of Otto’s famous book the moment he began reading it: When I first read Rudolph Otto’s “Idea of the Holy,” I understood it immediately in the light of these early experiences and took it into my thinking as a constitutive element. It determined my method in the philosophy of religion, wherein I started with the experiences of the holy and advanced to the idea of God and not the reverse way. Equally important existentially as well as theologically were the mystical, sacramental, and aesthetic implications of the idea of the holy, whereby the ethical and logical elements of religion were derived from the experience of the presence of the divine and not conversely.