"I believe in Spinoza's God who reveals himself in the orderly harmony of what exists, not in a God who concerns himself with the fates and actions of human beings." [Telegram of 1929, in Hoffman and Dukas]
"The religious feeling engendered by experiencing the logical comprehensibility of profound interrelations is of a somewhat different sort from the feeling that one usually calls religious. It is more a feeling of awe at the scheme that is manifested in the material universe. It does not lead us to take the step of fashioning a god-like being in our own image-a personage who makes demands of us and who takes an interest in us as individuals. There is in this neither a will nor a goal, nor a must, but only sheer being." [Dukas and Hoffman]
"But, on the other hand, every one who is seriously involved in the pursuit of science becomes convinced that a spirit is manifest in the laws of the Universe - a spirit vastly superior to that of man, and one in the face of which we with our modest powers must feel humble. In this way the pursuit of science leads to a religious feeling of a special sort, which is indeed quite different from the religiosity of someone more naive." [c. Dukas and Hoffman]
"The cosmic religious feeling is the strongest and noblest motive for scientific research. Only those who realize the immense efforts and, above all, the devotion without which pioneer work in theoretical science cannot be achieved are able to grasp the strength of the emotion out of which alone such work, remote as it is from the immediate realities of life, can issue. What a deep conviction of the rationality of the universe and what a yearning to understand. . . It is cosmic religious feeling that gives a man such strength." [The World as I See It]
"In human freedom in the philosophical sense I am definitely a disbeliever. Everybody acts not only under external compulsion but also in accordance with inner necessity." [The World as I See It]
"His [the scientist's] religious feeling takes the form of a rapturous amazement at the harmony of natural law, which reveals an intelligence of such superiority that, compared with it, all the systematic thinking and acting of human beings is an utterly insignificant reflection." [The World As I See It]
Also see Albert Einstein Online.