In Genesis 15, Abram knew what God was asking him to set up when he sacrificed the animals and let their blood drain down into the ravine. This was the age old ceremony of a marriage covenant. The groom's dad would walk through the blood. This action symbolized him saying, "if my son doesn't live up to everything I promise, you can have my head". Then the bride's dad would do the same. True to their word, blown covenants would warrant finding your loved one beheaded outside of town. So Abram knew the seriousness of the situation. He had asked God to prove to him that he would have an heir and continue the family bloodline. Seeing the number of stars was not enough. It required blood. Now, after some time of God not showing up, some birds came to prey upon the sacrifices and Abram had to run them off. I can almost hear their hissing accusations, probably ensenuating that God wasn't going to show up. Then when all was dark, a smoking firepot, representing God, passed through the blood. As it was customary, it was Abram's turn. Abram knew if he stuck a toe in that blood, he was a dead man. God surely could hold up His end of the deal, but Abram, being imperfect, could not come into a covenant with a perfect God. So God did the unthinkable: He passed through the blood a second time, this time as a flaming torch, on the behalf of Abram. It is believed at that point, God sentenced Jesus to die for the sins of mankind, for blood would be required for our lack of living up to our end of the deal. So Jesus walked through the blood for us, allowing us to be in a forever covenant with God Almighty. Amazing.
