Did God command Abraham to perform a human sacrifice?

One of the most well known Bible stories, often told in Sunday Schools, is that of Abraham and Isaac. Abraham is told by God that to prove his faith, he must take his son up to the top of a mountain, and kill him as a sacrifice. Abraham obeys, and just before delivering the killing blow, God stops him and tells him that he has passed the test, and his son can live.
This story rubs some people the wrong way, understandably so. However, what this short-hand version leaves out is the stuff that makes the terrifying command make a lot more sense. It's not unusual that someone who is only familiar with this version will ask "What would you do if God told you to kill someone you love?" expecting to put you in a catch 22 situation where you either have to admit you'd be willing to murder, or you'd be willing to disobey God. What is missing is a lot of important context. (Context, as usual).