Genesis 21:1-8

The LORD visited Sarah as he had said, and the LORD did to Sarah as he had spoken. Sarah conceived, and bore Abraham a son in his old age, at the set time of which God had spoken to him. Abraham called his son who was born to him, whom Sarah bore to him, Isaac. Abraham circumcised his son, Isaac, when he was eight days old, as God had commanded him. Abraham was one hundred years old when his son, Isaac, was born to him. Sarah said, “God has made me laugh. Everyone who hears will laugh with me.” She said, “Who would have said to Abraham that Sarah would nurse children? For I have borne him a son in his old age.” The child grew and was weaned. Abraham made a great feast on the day that Isaac was weaned.