http://www.submission.org/chri ... bible-contradictions.html
Knock yourself out. That's just one quick link I googled up. You should read "From Preacher to Atheist" by Dan Barker for a better source. Of course, every Christian always claims "context" when shown black and white contradictions.
I'm not being picky. I'm pointing out a glaring contradiction between what the bible says and what supposedly religious people teach. The ten commandments are exactly where I listed them, in Exodus 34:11. In Exodus 34:1 it reads "And the LORD said unto Moses, Hew thee two tables of stone like unto the first: and I will write upon
[these] tables the words that were in the first tables, which thou brakest." Moses gets two tables (stone tablets) and goes up the mountain. God then says, "Observe thou that which I command thee this day," then goes on to list ten things (which include never boiling a kid in its mother's milk, keeping a feast of unleavened bread, etc). "And he wrote upon the tables the words of the covenant, the ten commandments." (Exodus 34:28). The oft quoted "ten commandments" (thou shalt not kill, etc.) listed in Exodus 20 are never called commandments in the bible, and were never engraved on stone tablets.

And you're quite correct, Ishmael and Isaac are indeed the point of division, but the two faiths have gone in largely different directions since then.