And the angel of the LORD called unto him out of heaven, and said, Abraham, Abraham: and he said, Here Amos 1:1. And he said, Lay not thine hand upon the lad, neither do thou anything unto him: for now I know that thou fearest God, seeing thou hast not withheld thy son, thine only son from me.
This knowledge is not meant, as referring to God, but as proving the faith of his people to the world. Deuteronomy 8:2. But were not those three days during which Isaac lay under a sentence of death, until released by an order from heaven, typical of Christ's lying under death, until raised the third day from the grave? 1 Corinthians 15:3-4.