26 So the Lord said, "If I find in Sodom fifty righteous within the city, then I will spare all the place for their sakes." 27 Then Abraham answered and said, "Indeed now, I who am but dust and ashes have taken it upon myself to speak to the Lord: 28 Suppose there were five less than the fifty righteous; would You destroy all of the city for lack of five?" So He said, "If I find there forty-five, I will not destroy it." 29 And he spoke to Him yet again and said, "Suppose there should be forty found there?" So He said, "I will not do it for the sake of forty." 30 Then he said, "Let not the Lord be angry, and I will speak: Suppose thirty should be found there?" So He said, "I will not do it if I find thirty there." 31 And he said, "Indeed now, I have taken it upon myself to speak to the Lord: Suppose twenty should be found there?" So He said, "I will not destroy it for the sake of twenty." 32 Then he said, "Let not the Lord be angry, and I will speak but once more: Suppose ten should be found there?" And He said, "I will not destroy it for the sake of ten." 33 So the Lord went His way as soon as He had finished speaking with Abraham; and Abraham returned to his place.
Matthew Henry's Commentary on Genesis 18:26-33
Commentary on Genesis 18:23-33
(Read Genesis 18:23-33)
Here is the first solemn prayer upon record in the Bible; and it is a prayer for the sparing of Sodom. Abraham prayed earnestly that Sodom might be spared, if but a few righteous persons should be found in it. Come and learn from Abraham what compassion we should feel for sinners, and how earnestly we should pray for them. We see here that the effectual, fervent prayer of a righteous man avails much. Abraham, indeed, failed in his request for the whole place, but Lot was miraculously delivered. Be encouraged then to expect, by earnest prayer, the blessing of God upon your families, your friends, your neighbourhood. To this end you must not only pray, but you must live like Abraham. He knew the Judge of all the earth would do right. He does not plead that the wicked may be spared for their own sake, or because it would be severe to destroy them, but for the sake of the righteous who might be found among them. And righteousness only can be made a plea before God. How then did Christ make intercession for transgressors? Not by blaming the Divine law, nor by alleging aught in extenuation or excuse of human guilt; but by pleading HIS OWN obedience unto death.