The Lord is omniscient, so he didn't need to go down himself to see whether Sodom and Gomorrah sinned. He already knew. But he went down to see if Abraham would still be willing to offer up his own son, Isaac, as a sacrifice. God is also just, and he was going to punish the people of Sodom and Gomorrah for their wickedness. But he wanted to give them a chance to repent first. That's why he went down to see if they had sinned. If they had, then their punishment would have been swift and severe. But if they had repented, then their punishment would...