God wished to try Isaac also. Ishmael once boasted to Isaac, saying, "I was thirteen years old when the Lord spoke to my father to circumcise us, and I did not transgress His word, which He commanded my father." And Isaac answered Ishmael, saying, "What dost thou boast to me about this, about a little bit of thy flesh which thou didst take from thy body, concerning which the Lord commanded thee? As the Lord liveth, the God of my father Abraham, if the Lord should say unto my father, Take now thy son Isaac and bring him up as an offering before Me, I would not refrain, but I would joyfully accede to it."