What does Genesis 15:10 mean?
In response to Abram's request for reassurance that he and his offspring would possess the land as God had promised, the Lord told Abram to bring five specific animals before Him. Abram did so and now proceeds to cut the heifer, goat, and ram (all three years old) in half and to lay each half opposite the other. He did not cut the turtledove or pigeon in half.The symbolic meaning of this bloody-but-purposeful covenant ritual will be clarified in the following verses. In part, this meaning involves a unity of those making the agreement. According to some interpreters, this ritual was also used as a way of demonstrating sincerity; by implying that those passing between the pieces were willing to be destroyed, as the animals were, if they broke their part of the agreement. The use of the animals also provides Abram with a symbolic picture of Israel's future struggles under the oppressive rule of Egypt.
Genesis 15:1–21 falls between Abram's heroic rescue of Lot in Genesis 14 and his less-than-heroic choice to have a child with his wife's servant in chapter 16. Chapter 15 features Abram's hard questions to the Lord about how the lofty promises of uncountable descendants and possession of the land will be kept. God responds, in part, by formalizing His covenant promises to Abram with an elaborate ritual. He also reveals to Abram details about the difficult circumstances his descendants will face before they come back to take possession of the land ''in the fourth generation.''
Genesis 15 consists entirely of a long encounter between the Lord and Abram. When the ''word of the Lord'' comes to Abram in a vision to bring reassurance of God's support for him, Abram takes the opportunity to press God with questions. Abram asks both about his childlessness and how he can know he will one day possess the land of Canaan. God responds, and Abram believes. God's response includes leading Abram through a covenant ritual involving slaughtered animals, as well as a prophecy about the future of Abram's descendants before the time will come to occupy the Promised Land.