Here is what Richard Dawkins says about the story of Abraham and Isaac, in his book, The God Delusion.
Once again, modern theologians will protest that the story of Abraham sacrificing Isaac should not be taken as literal fact. And, once again, the appropriate response is twofold. First, many many people, even to this day, do take the whole of their scripture to be literal fact, and they have a great deal of political power over the rest of us, especially in the United States and in the Islamic world. Second, if not as literal fact, how should we take the story? As an allegory? Then an allegory for what? Surely nothing praiseworthy. As a moral lesson? But what kind of morals could one derive from this appalling story? Remember, all I am trying to establish for the moment is that we do not, as a matter of fact, derive our morals from scripture. Or, if we do, we pick and choose among the scriptures for the nice bits and reject the nasty. But then we must have some independent criterion for deciding which are the moral bits: a criterion which, wherever it comes from, cannot come from scripture itself and is presumably available to all of us whether we are religious or not.Apologists even seek to salvage some decency for the God character in this deplorable tale. Wasn't it good of God to spare Isaac's life at the last minute? In the unlikely event that any of my readers are persuaded by this obscene piece of special pleading, I refer them to another story of human sacrifice, which ended more unhappily. Judges, chapter 11, the story of Jephthah and his daughter.