Genesis 21:1-7 ASV

1 And Jehovah visited Sarah as he had said, and Jehovah did unto Sarah as he had spoken.
2 And 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.
4 And Abraham circumcised his son Isaac when he was eight days old, as God had commanded him.
5 And Abraham was a hundred years old, when his son Isaac was born unto him.
6 And Sarah said, God hath made me to laugh. Every one that heareth will laugh with me.
7 And she said, Who would have said unto Abraham, that Sarah should give children suck? For I have borne him a son in his old age.