I find it interesting that this chapter starts with God saying:
“Do not be afraid Abram…”
This was after Abraham had returned victorious from saving Lot from the army that kidnapped him. Why did this not happen after Abraham had lied to Pharaoh because of his fear? It happened after Abraham had apparently been brave…
The verse continues saying that God would be Abraham’s great reward – which Abraham interpreted as wealth because he said that this did not really matter since God had not given him an heir so his estate would not remain in his family. But I wonder at this promise of “great reward” when Abraham had already achieved (presumably through God’s blessing) great wealth.
So we start this chapter with God promising two things that it seems Abraham had already – courage and wealth. God then promised He would provide Abraham with a son and made a covenant with him confirming the inheritance of the land of Canaan for his descendants. The latter two things were almost unbelievable to Abraham but he did believe that God would give him a son, and this is quoted later in Hebrews because Abraham is “credited with righteousness” because he believed God. But he asked God to prove the promise of the land and God covenanted with Abraham over this.
He explained that the cutting in half of animals was part of contractual law at the time. Parties or one party wishing to be bound in a contract would walk between the two halves of the animals saying, in effect, may I be cut in two like this should I break this contract. What is interesting here is that God, in the form of the blazing torch, passed between the carcass halves and Abraham did not. This made a unilateral covenant between God and Abraham and his descendants that He would give them the land from “the Wadi of Egypt to the great river, the Euphrates.” (verse 18). God did not require Abraham’s contractual obligation for this covenant.
This is a rather confusing chapter – firstly Abraham was promised stuff he had, then he was promised a son and believed God, then God promised him the land and he asked God to “prove it” … yet it does summarise the fluctuations in Abraham’s relationship with God from Abraham’s side and the steadfast faithfulness of God to him regardless. This is much like my relationship to God.