Genesis 18:26-28

And the LORD said, If I find in Sodom fifty righteous within the city, then I will spare all the place for their sakes. And Abraham answered and said, Behold now, I have taken upon me to speak unto the Lord, which am but dust and ashes: peradventure there shall lack five of the fifty righteous: wilt thou destroy all the city for lack of five? And he said, If I find there forty and five, I will not destroy it.