I'm in the process of studying various aspects of the religion of Islam, and one thing I've wondered about is how it views Abraham's son Isaac. I've been told that Islamic people claim to be descended from Abraham through Ishmael. I'm familiar with what our Bible says about Ishmael, but I'm wondering if there is any Islamic text (either the Koran or some other writing) that says anything about Isaac. If so, what does it say about Ishmael's half brother? Any information any of my BB friends could supply me with on this would be appreciated.