James was no atheist, and did believe that one could find evidence for God, but he thought theology was useless in adducing that evidence. In his classic book The Varieties of Religious Experience (1902, based on the previous year’s Gifford Lectures in Edinburgh), he argues that religious “truth” emanates from a consciousness different from our normal rational consciousness, and that “truth” about the divine is produced by revelation and then verified by its salutary effects on human behavior. There are many problems with his arguments, which I won’t go into here, but at least the man had no truck with theologians. This is from p. 436 of the 1928 edition, where he talks about the philosophy of religion, that is, theology:
“I believe, in fact, that the logical reason of man operates in this field of divinity exactly as it has always operated in love, or in patriotism, or in politics, or in any other of the wider affairs of life, in which our passions or our mystical intuitions fix our beliefs beforehand. It finds arguments for our convictions, for indeed it has to find them. It amplifies and defines our faith, and dignifies it and lends it words and plausibility. It hardly ever engenders it; it cannot now secure it.”
Shorter version: theology is the post hoc rationalization of what you want to believe.