When he returned to London he fingered and skimmed his way through a dozen religious theories of the time, but emerged in the clear (voyant trop pour nier, et trop pen pour s'assurer) a healthy agnostic.* What little God he managed to derive from existence, he found in Nature, not the Bible; a hundred years earlier he would have been a deist, perhaps even a pantheist. In company he would go to morning service of a Sunday; but on his own, he rarely did.
[* Though he would not have termed himself so, for the very simple reason that the word was not coined (by Huxley) until 1870; by which time it had become much needed.]