Hi newgene,
If you will notice in reading this passage, it was Abraham who came up with the numbers. God had spoken that He was going to go see if it was that bad.
Gen 18:21 I will go down now and see whether they have done altogether according to the outcry against it that has come to Me;
It was Abraham that began to entreat God by saying, (23) "Would You also destroy the righteous with the wicked? (24) Suppose there were fifty righteous within the city; would You also destroy the place and not spare it for the fifty righteous that were in it?" Then God said no to this number (50) and all the rest of the numbers that Abraham came up with. So it was Abraham that was working out in his own mind what he thought it would take to save this wicked city. Araham must have thought that 50 was a reasonable amount to save a city for, but quickly re-thought that number, knowing the city and ask for less, and kept going down, because he must have known how bad the city truly was.
But God knew all along that there was none righteous there and was just hearing Abraham out, even though He knew it would be destroyed. God was Patient with Abraham and let him prove to himself that there was really none (even though he stopped at 10, he knew there was none) that were righteous in the city.
I think this is a good repersentation of the few and the many. Sodom & Gomorrah is like the world/many, like Olasupo posted,
Rom 3:10 As it is written: "There is none righteous, no, not one;
Then there is Lot and his family a very few that escaped the wrath and went into the mountains. But even there we see one that did not endure to the end.
Gen 19:26 But his wife looked back behind him, and she became a pillar of salt.
Luke 9:62 But Jesus said to him, "No one, having put his hand to the plow, and looking back, is fit for the kingdom of God."
Just thought I would throw that bit in there about "looking back" since it was part of this story.
mercy, peace and love
Kat