"So Sarah laughed to herself..."
I love that she laughs. I love it more that she is called out on it in verse 15 and, because she is human, denies it! Sarah, like Abraham, realizes how crazy this whole notion of her bearing child really is. She realizes that it would be a miracle for her to bear a child.
Sometimes hope seems crazy. Sometimes people look at the hope we have in Christ and think, "That's crazy. You really believe that?" Yes. I do. I have hope in Christ because there's nothing and no one else who can save. There is nothing and no one else in which I trust with my hope for the future. But sometimes we have to laugh because we are human. Sometimes we think about our hope compared the hopes of the world, and we have to laugh. We must look crazy! We are fools for Christ! We are, as Paul said, putting our faith in what is foolishness to the world. And there is no better place, more right place, to place our hope! Praise be to God.
God's mercy exhibited. God's promise to Abraham fulfilled; that is, if he could find anyone who was righteous in Sodom and Gomorrah he would save them. So even when Lot is "lingering," the Lord "seizes him and his wife and his two daughters by the hand." Why? "The LORD was merciful to him." For all the times God gets painted as one who is full of wrath and smite in the Old Testament, there are texts like this one. There are texts that say, "God is merciful. God is full of grace. God is slow to anger. God is love." Again, God, who created all of this, has every right to wipe it all out, but God, because he is merciful, loving, and full of grace, chooses to extend pardon. God chooses to embrace people who don't deserve it. This is grace. This is the Good News!
Quick note to cap off a pretty messed up story involving incest...Look at the nations founded through this messiness: the Moabites and Ammonites. Look at Jesus' genealogy in Matthew. Ruth, the Moabite, is among the ancestors of Jesus. Once again God shows that he can take messy situations, sinful situations, and redeem them. Praise God that he is able to redeem and restore us. He heals our brokenness.