Genesis 17:17-19

"Then Abraham fell on his face and laughed, and said in his heart, 'Shall a child be born to a man who is one hundred years old? And shall Sarah, who is ninety years old, bear a child?'"

"And Abraham said to God, 'Oh, that Ishmael might live before You!'"

"Then God said: 'No, Sarah your wife shall bear you a son, and you shall call his name Isaac; I will establish My covenant with him for an everlasting covenant, and with his descendants after him.'"