In this chapter, Abraham is told to leave everything he has (his property, his friends, and his family) and to embark on a journey to . . . nobody knows. Why does Abram do this? Is it because God tells him to? Probably not. Abram probably only does this because God promises to "make his name great." Remember in the story of the Tower of Babel (one chapter before this) how people tried to make a name for themselves on their own? Well, now God comes downs and essentially says, "It's okay to have a name; it's just not okay to make it for yourself. You're going to need my help, and you're going to have to want my help." This hypostatic extension, however, is very vague, still. How will he have a name for himself? Well, God says that all the nations will be blessed through him. That's certainly a good place to start. THe nations will be blessed through him in that Abraham is the one through whom God reveals the way to Him. Before, everybody was just guessing what to do. Abraham is the guy that reveals how to deal with God.
Verse 7 is where we finally figure out what the promised land is. It's Canaan. When he finally gets to Canaan, Abraham invokes the name of the Lord, or in other words, he hypostatically extends God's name to his altar. So, while God promised hypostatic extension to Abraham, Abraham is giving the same back to God, which I find very interesting.
Now, Abraham takes Lot along with him on his journey. God specifically told Abraham, however, to leave his family behind. This is Abraham's first mistake, and our first look into his character. Abraham just does not have enough faith or does not care enough to follow God's commandments, and Lot comes back to haunt Abraham later.
A famine settles over the land of Canaan. Now, once again, Abraham, without conslulting God, Abraham decides to leave the promised land. Once again, this shows his lack of faith in God. He didn't think Canaan was good enough. After all, it was suffering from famine, and Egypt is the breadbasket of the world, not Canaan. So, off he goes to Egypt.
When he gets to egypt, you see the first wife/sister scene. He tells Sarai to just say that they are brother and sister. He reasons that if the Pharaoh knew they were married, he would kill Abram to get Sarai. (but is this really true? Apparantly not) So, they follow through with this. This is where Abraham really gets low, though. The Pharaoh doesn't have like a toll booth at the beginning of Egypt. Yet the Pharaoh's men managed to find out about the beauty of Sarai, and that she was available. Abram was advertising this. Why? The meaning becomes clear when you read the Pharaoh's reaction to getting Sarai. He blesses Abraham for allowing him to have Sarai. Abram pimped Sarai out for his own gain. And then, when the Pharaoh finds out that Sarai and Abram are married, he gets mad, but doesn't kill them. He just exiles them. Lo and behold, they end up back in Canaan, the promised land. (This is also probably how they end up with Hagar, the Egyptian slave.) Abram is not that great of a guy, or so it seems.
Lot and Abram now seperate. Abram gives Lot his choice of land. He chooses the good land. Lot is causing Abraham problems (since he wasn't supposed to be brought along anyway).