There is some fascinating information in our Genesis passage that we miss out on because of not understanding Jewish culture. I first heard this in a Ray Vanderlaan lecture online and was able to find this description from another blog.....
Abram knows exactly what to do because this is a common practice in the world of covenants. They are setting up what is called a bloodpath covenant. This is a covenant sign that is often used in Abram's day to signify a betrothal (engagement) covenant. Those very animals are used, cut in half, and arranged opposite one another on opposing slopes. Here is a picture of what the covenant looks like:
The arranged halves create a path of blood in between the animals. I will use the example of a betrothal to explain the ceremony. As the two parties agree to the marriage, the lesser party (in the example, this would be the future groom; he is asking the father of the future bride to marry his daughter) dons a white robe and then passes through the path of blood. As the blood splashes up on his white robe, the symbolic statement is, "If I mistreat or abuse your daughter, you may do this in my blood". After this, the father dons a white robe and passes through the blood path, saying, "If I do not supply you with a virgin for a daughter, you may do this in my blood".
It's the collateral covenant that allows for the parties to be held liable for their promises.
God sets up an engagement covenant for Abram.
Now, whose move is it? Who is the lesser party? Abram is, obviously.
But Abram doesn't pass through the halves. In fact, he chases away the vultures. What does that tell you? This ceremony has been set up for some time.
But Abram knows that he'll never be able to keep his end of the covenant. He won't be able to live obediently for God for the rest of his days.
If Abram's little toe hits the bloodpath, he's a dead man.
And so God puts him in a deep sleep (the same sleep He put Adam in, by the way) and, while Abram is greatly distressed and troubled, Abram sees a flaming torch and smoking pot pass between the halves. Now, fire and smoke always symbolize the presence of God (think the pillar of fire/smoke). So what does Abram see?
God is passing through the covenant halves — twice.
God passes through the halves on behalf of Abram.
In other words, "Abram, when you fall short, I will cover your shortfall. We will pay for it in my blood."
That's incredible. And every Christian immediately sees Jesus in this story.
But I would make this point. It's not just that this story is a foreshadowing of Jesus. It's that this is who God has ALWAYS been. God has ALWAYS taken our sin on Himself. God has ALWAYS covered our shortfall. This is who God is. There is no "God of the Old Testament" and "God of the New Testament". He always has been the same God.
His message has always been the same: "I am God. I love you. I am for you. I will fight for you in spite of yourself."
Tomorrow's Bible In a Year Passage: Genesis 16:1-18:15, Matthew 6:1-24, Psalm 7:1-17, Proverbs 2:1-5