Suppose there is a God who a long, long time ago spoke to Abraham, promising to bless the world through his descendants. Suppose his descendants told their friends who told their friends who told their friends about Abraham’s encounter with God, with some of those friends identifying as Jews, some as Christians, and some as Muslims. Their descriptions agree in many respects, even important ones — they all believe, for example, that God is one, merciful, just and Creator. Their descriptions of God also differ in some respects. Christians, for example, think that God was incarnate in Jesus while Muslims and Jews reject the Trinity. And they, Muslims-Christians-Jews, even call God different names — among them, Yahweh, the Father and Allah.