Genesis 18:28 ASV

²⁶  And Jehovah said, If I find in Sodom fifty righteous within the city, then I will spare all the place for their sake.

²⁷  And Abraham answered and said, Behold now, I have taken upon me to speak unto the Lord, who am but dust and ashes:

²⁸  peradventure there shall lack five of the fifty righteous: wilt thou destroy all the city for lack of five? And he said, I will not destroy it, if I find there forty and five.

²⁹  And he spake unto him yet again, and said, Peradventure there shall be forty found there. And he said, I will not do it for the forty's sake.

³⁰  And he said, Oh let not the Lord be angry, and I will speak: peradventure there shall thirty be found there. And he said, I will not do it, if I find thirty there.