age for the children that god had promised. he had already been told to send his first son ishmael away. now only isaac was left at home. >> abraham, for better or for worse, is used to hearing god's voice. and one day, as the torah tells us in genesis 22, god decides to test abraham. and he says, take your son. your only son. whom you love, and offer him as a sacrifice at the place that i will show you. >> god was telling abraham to kill his own son. ♪ >> you would think that that story is so barbaric that it would have died out over time. instead, jews read it in their holiest week of the year on rosh hashanah. christians read it, the same story, in their holiest week of the year, on easter.