Do you know Darwin started by studying religion? He was studying at Christ’s College, Cambridge in 1827 for a Bachelor of Arts degree as the qualification required before taking a specialised divinity course and becoming an Anglican parson? He studied William Paley’s Evidences of Christianity, becoming so delighted with Paley’s logic that he learnt it well.

“Darwin’s discovery caused him great, personal grief and serves as an exemplar of a scientist following the evidence wherever its leads and whatever the consequences.”
– God: The Failed Hypothesis: How Science Shows That God Does Not Exist by Victor J. Stenger, Christopher Hitchens

In one 1860 letter to Gray, Darwin expressed his doubts about the teleological argument which claimed nature as evidence of god, though he was still inclined to vaguely believe in an impersonal God as first cause:[60]

With respect to the theological view of the question; this is always painful to me.— I am bewildered.– I had no intention to write atheistically. But I own that I cannot see, as plainly as others do, & as I [should] wish to do, evidence of design & beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent & omnipotent God would have designedly created the Ichneumonidæ with the express intention of their feeding within the living bodies of caterpillars, or that a cat should play with mice. Not believing this, I see no necessity in the belief that the eye was expressly designed. On the other hand I cannot anyhow be contented to view this wonderful universe & especially the nature of man, & to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton.— Let each man hope & believe what he can. – Darwin, Wikipedia