I believe it is not only permissible but a religious obligation to question the existence of God if you are troubled by some of the things you were taught, to question the divine origin of things that are said in God’s name, and then to go on and search for answers to your questions. The only religiously unacceptable response is to reject religion entirely and close your mind to further speculation. I cannot believe that God would bless us with a critical intelligence, with the ability to extend the frontiers of knowledge and understanding when it comes to biology and psychology, and then say to us, “Stop, go no further” when it comes to theology. For me, the alternative to faith is not doubt but despair, the conclusion that we are alone in a cold and unreliable world.
— Harold S. Kushner, Nine Essential Things I’ve Learned About Life, p. 120-121.