Genesis 17:15-19 Gen. 17:15-19
15 And God said unto Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be. 16 And I will bless her, and give thee a son also of her: yea, I will bless her, and she shall be a mother of nations; kings of people shall be of her. 17 Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear? 18 And Abraham said unto God, O that Ishmael might live before thee! 19 And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him.
Genesis 21:1-3 Gen. 21:1-3
1 And the LORD visited Sarah as he had said, and the LORD did unto Sarah as he had spoken. 2 For Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him. 3 And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac.
(Prophecy)