If one's first name is Schlomo or Moishe, it's more than likely that one is Jewish. But Abraham???
Granted that Abraham is considered a stereotypical Jewish name. But... Abraham Lincoln???
No, no, no, four score and seven times no, Abraham Lincoln was not even remotely Jewish. And just to get it out of the way, neither are French mathematician Abraham de Moivre, Swiss watchmaker Abraham-Louis Breguet, Mexican revolutionary Abraham Gonzalez, Indian professor Abraham Kovoor, Mormon pioneer Abraham O. Smoot, Dutch painter Abraham Bloemaert, or Dominican baseball player Abraham Nunez.
Now, there is a theory that Lincoln had Jewish roots, many many generations ago, something to do with the town of Lincoln in England... But those are just theories, flimsy as best.
But if you take those as truth, and start digging centuries deep, who knows what possibilities you'd encounter... Perhaps that all the aforementioned Abrahams had a Jewish ancestor at some point?
The original Abraham, maybe?