James H. Matheny says in a letter to Mr. Herndon:—
"I knew Mr. Lincoln as early as 1834-7; know he was an infidel. He and W. D. Herndon used to talk infidelity in the clerk's office in this city, about the years 1837-40. Lincoln attacked the Bible and the New Testament on two grounds: first, from the inherent or apparent contradictions under its lids; second, from the grounds of reason. Sometimes he ridiculed the Bible and New Testament, sometimes seemed to scoff it, though I shall not use that word in its full and literal sense. I never heard that Lincoln changed his views, though his personal and political friend from 1834 to 1860. Sometimes Lincoln bordered on atheism. He went far that way, and often shocked me. I was then a young man, and believed what my good mother told me. Stuart & Lincoln's office was in what was called Hoffman's Row, on North Fifth Street, near the public square. It was in the same building as the clerk's office, and on the same floor. Lincoln would come into the clerk's office, where I and some young men—Evan Butler, Newton Francis, and others—were writing or staying, and would bring the Bible with him; would read a chapter; argue against it. Lincoln then had a smattering of geology, if I recollect it. Lincoln often, if not wholly, was an atheist; at least, bordered on it. Lincoln was enthusiastic in his infidelity. As he grew older, he grew more discreet, didn't talk much before strangers about his religion; but to friends, close and bosom ones, he was always open and avowed, fair and honest; but to strangers, he held them off from policy. Lincoln used to quote Burns. Burns helped Lincoln to be an infidel, as I think; at least, he found in Burns a like thinker and feeler. Lincoln quoted 'Tam O'Skanter.' 'What! send one to heaven, and ten to hell!' &c.
"From what I know of Mr. Lincoln and his views of Christianity, and from what I know as honest and well-founded rumor; from what I have heard his best friends say and regret for years; from what he never denied when accused, and from what Lincoln has hinted and intimated, to say no more,—he did write a little book on infidelity at or near New Salem, in Menard County, about the year 1834 or 1835. I have, stated these things to you often. Judge Logan, John T. Stuart, yourself, know what I know, and some of you more.
"Mr. Herndon, you insist on knowing something which you know I possess, and got as a secret, and that is, about Lincoln's little book on infidelity. Mr. Lincoln did tell me that he did write a little book on infidelity. This statement I have avoided heretofore; but, as you strongly insist upon it,—probably to defend yourself against charges of misrepresentations,—I give it you as I got it from Lincoln's mouth."
From Hon. John T. Stuart:—
"I knew Mr. Lincoln when he first came here, and for years afterwards. He was an avowed and open infidel, sometimes bordered on atheism. I have often and often heard Lincoln and one W. D. Herndon, who was a freethinker, talk over this subject. Lincoln went further against Christian beliefs and doctrines and principles than any man I ever heard: he shocked me. I don't remember the exact line of his argument: suppose it was against the inherent defects, so called, of the Bible, and on grounds of reason. Lincoln always denied that Jesus was the Christ of God,—denied that Jesus was the Son of God, as understood and maintained by the Christian Church. The Rev. Dr. Smith, who wrote a letter, tried to convert Lincoln from infidelity so late as 1858, and couldn't do it."
William H. Herndon, Esq.:—
"As to Mr. Lincoln's religious views, he was, in short, an infidel,... a theist. He did not believe that Jesus was God, nor the Son of God,—was a fatalist, denied the freedom of the will. Mr. Lincoln told me a thousand times, that he did not believe the Bible was the revelation of God, as the Christian world contends. The points that Mr. Lincoln tried to demonstrate (in his book) were: First, That the Bible was not God's revelation; and, Second, That Jesus was not the Son of God. I assert this on my own knowledge, and on my veracity. Judge Logan, John T. Stuart, James H. Matheny, and others, will tell you the truth. I say they will confirm what I say, with this exception,—they all make it blacker than I remember it. Joshua F. Speed of Louisville, I think, will tell you the same thing."
Hon. David Davis:—
"I do not know any thing about Lincoln's religion, and do not think anybody knew. The idea that Lincoln talked to a stranger about his religion or religious views, or made such speeches, remarks, &c., about it as are published, is to me absurd. I knew the man so well: he was the most reticent, secretive man I ever saw, or expect to see. He had no faith, in the Christian sense of the term,—had faith in laws, principles, causes, and effects—philosophically: you [Herndon] know more about his religion than any man. You ought to know it, of course."