God said to Abraham, ‘As for Sarai your wife, you shall not call her Sarai, but Sarah shall be her name. I will bless her, and moreover I will give you a son by her. I will bless her, and she shall give rise to nations; kings of peoples shall come from her.’ Then Abraham fell on his face and laughed, and said to himself, ‘Can a child be born to a man who is a hundred years old? Can Sarah, who is ninety years old, bear a child?’

The Lord said to Abraham, ‘Why did Sarah laugh, and say, “Shall I indeed bear a child, now that I am old?” Is anything too wonderful for the Lord? At the set time I will return to you, in due season, and Sarah shall have a son.’ But Sarah denied, saying, ‘I did not laugh’; for she was afraid. He said, ‘Oh yes, you did laugh.’

Abraham was a hundred years old when his son Isaac was born to him. Now Sarah said, ‘God has brought laughter for me; everyone who hears will laugh with me.’

Genesis 17:15-17; 18:13-15; 21:5-6