And I question the character of a man who questions the character of a man who he doesn't really know. Lincoln's spiritual beliefs were complex and perhaps unorthodox, but they were there.
In Doris Kearns Goodwin's seminal work on Lincoln "Team of Rivals," she quotes Ward Lamon, a Lincoln supporter and friend, as saying that the President had a premonition of his assassination in one of his dreams right before his tragic journey to Ford's Theatre. Lamon says that Lincoln said he saw a "corpse whose face was covered while others weeped pitifully." Lincoln seeing the corpse demanded that the ceremonial guard tell him who was laying in state. "The President" was his answer, "he was killed by an assassin!"
Lamon said the President tried to "evade the portent of the dream" by trying to comfort Lamon that it wasn't him in the dream "but some other fellow that was killed..." The President then says to Lamon "I think the Lord in his own good time and way will work this out alright. God knows what is best."
At least one major Lincoln biographer has questioned Lamon's chronology of events and thus whether this story is accurate.
That Lincoln rarely attended church services, and never joined a Congregation is not in doubt. However Lincoln was very converant with the bible, and claimed to be a Christian.