lc,
You're right about one thing. All the stories are Very contradictory. You can read one thing saying he was a believer, yet not a practitioner. The next article says he was more religious than not, and then you have Herndon, who knew and was close to Lincoln his entire life, saying he was an infidel and bordered on being atheist. It is obvious the man was a "fatist" and did not believe in prayer.
Gw is right about the seances Mary Lincoln had in the White House. That was pretty much common knowledge.
I'm gonna go with Herndon, since he knew Lincoln probably Longer and Better than anybody else alive. He was with him almost all the time, even throughout his presidency, so he would tend to have a lot more insight as to how the man felt about everything, especially religion. As I'm fond of saying... He was there.
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I can't help but wonder how all this affected his decision making during his presidency...
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SBG