“And he said, Take now thy son, thine only son Isaac, whom thou lovest, and get thee into the land of Moriah; and offer him there for a burnt offering upon one of the mountains which I will tell thee of.”
God says to take his son, his only son, whom he loves — Isaac — and go to the region of Moriah and sacrifice him as a burnt offering on a mountain he will show him. The command is devastating in its specificity: four increasingly particular identifications of what is being asked for. There is no way to reconcile the command with the promise by human logic — only by trusting the God who gives both. Hebrews 11:19 interprets Abraham's reasoning: he figured God could raise the dead. The application: the test of faith is always whether you trust the God who gives the promise more than your own understanding of how it will be kept.