Background

God's covenant with Abraham gives us the first glimpse into God's specific plans for building His Kingdom on earth.  Until this point, God's desire to glorify Himself (Num. 14:21) by establishing a kingdom of humans on earth (Matt. 6:10) had been continually rejected by man.  They did not follow God's command to fill the earth (Gen. 9:1) and instead chose to congregate together (Gen 11:1-2). At the Tower of Babel, God forced mankind to fill the earth by confusing their languages (Gen. 11:8).

In this newly divided world, God chooses Abraham - a pagan man whose father worshipped idols (Josh 24:2) - as the recipient of His promises to continue His kindgom program and restore the earth.

The Promise

God first appears to Abraham while he is living in Ur with his family (Acts 7).  He tells Abraham to leave his country, people, and family and to move to "a land that I will show you." God then gives him a series of promises sumarized below (Gen 12:1-3):

1. I will make you into a great nation
2. I will bless you
3. I will make your name great and you will be a blessing
4. I will bless those who bless you and curse those who curse you.
5. [I will make] all peoples on earth blessed through you.

Abraham is not quick in obeying though - he makes several mistakes including stopping in Haran and taking his family with him (Gen. 11:4-5), travelling to Egypt, and lying about his wife Sarah (Gen. 11:10-12), showing little faith in God's protection.  Still, when Abraham responded in obedience, God reiterated these promises (Gen. 11:7, 13:14-17, note that God says His covenant is "everlasting").

The Covenant

Through Abraham's mistakes and growing obedience in chapters 11-14, God never wavers in his promises to Abraham.  In chapter 15, God formally announces what He will do through Abraham in the form of a blood covenant.  When God comes to him, Abraham asks how he can be the father of a nation without a son (Gen. 15:2-3).  Would the promise go to another (Eliezar)?

God again repeats his promises to create a great nation from Abraham's line (Gen. 15:5).  Abraham then places his faith in God as the sole source of this provision, and God counts this faith as righteousness (Gen. 15:6).  After Abraham's profession of faith, God directs Abraham to set up a blood covenant (Gen. 15:9-11), but instead of allowing Abraham to participate, Abraham falls into a deep sleep (Gen. 15:12), and God alone passes between the animals (Gen. 15:17).  This signifies that God is the sole responsible party in bringing about the fulfillment of all the promises of the covenant. 

This covenant brings together all God's previous promises to Abraham:

1. Land (Gen. 13:14-15; 15:18-21) - that the nation of Israel would occupy a land of their own.
2. Seed (Gen. 12:2; 13:16; 15:4-5) - that a great nation would come through Abraham.
3. Blessing (Gen. 12:2-3; 15:15) - that all the nations of the earth would be blessed through Abraham.

The Abrahamic Covenant is an unilateral (God alone is responsible Gen. 15:12, 17), unconditional (there is "if you..." only God's "I will" Gen. 12:2-3; 13:14-16; 15:5, 18-21), and eternal (Gen. 13:15; 17:7, 13, 19).