In this chapter, Abram seems to be having a bit of a faith crisis. After many years of struggling with infertility, he is questioning how God is planning to give him many descendants. God reassures Abram that he will keep his promise. We are told that Abram believed God, so God considered Abram righteous. This verse is referenced in Roman 4:3, 22 and 23 and Galatians 3:6 to show us that it is faith which makes us right with God, and James 2:23 tells us faith also leads to righteous living. The ceremony of God passing between the halves of the dead animals is saying God would have to die like these animals before it would be possible for God not to keep his promise. That’s a pretty strong promise! It shouldn’t have been necessary for God to confirm his promise this strongly, but God meets Abram in his weakness.
Here and in chapter 12, we see Abram struggling with his faith while at other times being strong. My faith is sometimes weak and sometimes strong too, but God always remains faithful. Faith is the first step in entering into a relationship with God, but that doesn’t mean our faith never wavers. If I want to stay close to God, I need more faith.