“And he took unto him all these, and divided them in the midst, and laid each piece one against another: but the birds divided he not.”
King James Version (KJV)
15:8 Whereby shall I know that I shall inherit it? - This did not proceed from distrust of God's power or promise, but he desired this, For the strengthening of his own faith. He believed, #Ge 15:6|, but here he prays, Lord help me against my unbelief, Now, he believed, but he desired a sign, to be treasured up against an hour of temptation. For the ratifying of the promise to his posterity, that they also might believe it.
15:9 Take me an heifer - Perhaps Abram expected some sign from heaven, but God gives him a sign upon a sacrifice. Those that would receive the assurances of God's favour, must attend instituted ordinances, and expect to meet with God in them. Observe, God appointed that each of the beasts used for his service should be three years old, because then they were at their full growth and strength. God must be served with the best we have. We do not read that God gave Abram particular directions how to manage these, knowing that he was well versed in the custom of sacrifices. Abram took as God appointed him, though as yet he knew not how these things should become a sign to him. He divided the beasts in the midst, according to the ceremony used in continuing covenants, #Jer 34:18|,19, where it is said, they cut the calf in twain, and passed between the parts. Abram, having prepared according to God's appointment, set himself to expect what sign God would give him by these.
15:12 And when the sun was going down - About the time of the evening oblation. Early in the morning, while the stars were yet to be seen, God had given him orders concerning the sacrifices, #Ge 15:5|, and we may suppose it was at least his morning's work to prepare them, and set them in order; which when he had done, he abode by them praying and waiting 'till towards evening. A deep sleep fell upon Abram - Not a common sleep through weariness or carelessness, but a divine extasy, that being wholly taken off from things sensible, he might be wholly taken up with the contemplation of things spiritual. The doors of the body were locked up, that the soul might be private and retired, and might act the more freely. And lo, a horror of great darkness fell upon him - This was designed to strike an awe upon the spirit of Abram, and to possess him with a holy reverence. Holy fear prepares the soul for holy joy; God humbles first, and then lifts up.