Genesis 18:28

Peradventure. The patriarch presented his case with adroit Oriental tact. His first hypothetical estimate of the number of pious Sodomites was designedly high enough to elicit a favorable response. Realizing, however, that this number was probably too high, he again showed rare diplomacy. Instead of pleading for the city’s safety on the basis of 45 just persons, he protested the thought that it might be destroyed on account of the lack of 5. Encouraged by the continued gracious response of God, he grew bolder, gradually diminishing the number of righteous persons which, in his opinion, should be sufficient to save the city.

Abraham did not request the unconditional sparing of the city, but only its preservation on certain conditions. It would be rash to speculate as to what would have happened had he continued, and reduced the number to less than ten. Perhaps Abraham felt safe in letting the number stand there; besides Lot, his wife, and two daughters at home, were there not Lot’s married daughters and their families also (see ch. 19:14, 15)? Starting out with a number he deemed likely to elicit a favorable response, it is probable that Abraham originally intended to decrease it so long as there appeared to be hope of securing such a response. And divine mercy met Abraham’s intercession without hesitation.