What a mess this crew is. Lot gives his daughters to the crowd, Abraham imperils Sarah to save his own hide, Jacob snakes his brother, echoing the division between his parents, then tries to make peace at the end with grampa's trick, putting the women and children in danger first. As karrde points out in the Joseph comments, the story of Dinah is pretty grim, and I haven't even gotten to Laban. When the Lord uses the traditional identifying formula later in scripture The God of Abraham, of Isaac, and of Jacob, it's not such a warm fuzzy. Jews of a reflective nature might well have thought Do you have to keep bringing that up? It's nice and homey that you're the family god and all that, but ouch! Couldn't you have mentioned some of our good guys?
God's intent - or one of His intents, as there are always wheels within wheels with Him - is pretty clear. Not because of who you are, but because of who I Am. Got it? Well, there's an odd comfort in it, I guess, when you are feeling lower than low, you still know you're chosen.
I'd like to give this motley band a little credit. All the tribesmen called out of Ur have grown up in a polygamous, polytheistic, card-sharping land that includes Sodom and Gomorrah as its cities of light. God pounds in a very few lessons early on, pretty much letting everything else go. Rule #1: Follow me. Just me. No one else, just me. Have you got that? I am your god, all those other gods are for other people, not you. Hands off.
This is about the only lesson that Lot ever learns. He's pretty much a scum, but he gets that one idea drummed into his head. This god. Not those other gods I grew up with. Only one.
It sounds easy to us now, but it wasn't easy for them. When Christianity came to Europe, the worship of older gods hung on for centuries. When people wanted their crops to grow, or their children to recover, they would sneak back to the old altars and make the old sacrifices. When your back is against the wall, you pretty easily slip into thinking maybe the old way is more powerful. Maybe this new religion doesn't work here, or doesn't work at all.
Including human sacrifice, which became Rule #2: no human sacrifice. But gee, everyone around here does that in a pinch, Lord. All the tribes are doing it. It's powerful. It shows commitment. The blood of a living creature appeases the uh, Other Forces, and humans are like really, really valuable. God teaches this people: But not you. This act is forbidden you. I am more pleased with other things - see Rule #1.
Hints of other rules to come are scattered in the stories of Abraham, Isaac, and Jacob, but these are the big two. And compared to how badly Europe and every other tribe in the world has done when God's teaching comes to them, three generations is pretty quick. It may be a record.