From The Advocate in Louisiana comes this interesting letter looking at the common confusion of quoting Shakespeare, Lincoln and the Bible. It caught my eye because while discussion of Shakespeare vs the Bible is quite common, I don't often hear Lincoln thrown in there. As a matter of fact I had no idea that Lincoln was a Shakespeare fan (apparently Macbeth was his favorite play, and John Wilkes Booth had played Macbeth).
Unlike many articles on the subject, however, the author does not answer any of his "Who said it first" questions. So you're not going to learn anything new. As a matter of fact the whole letter is actually written by a commitee member for the Lincoln Bicentennial.