But your son Isaac will be born about this time next year, and the promise I am making to you and your family will be for him and his descendants for ever.
One of the guests was the LORD, and he said, “I'll come back about this time next year, and when I do, Sarah will already have a son.” Sarah was behind Abraham, listening at the entrance to the tent.
Abraham had been promised that Isaac, his only son, would continue his family. But when Abraham was tested, he had faith and was willing to sacrifice Isaac,