This is another excerpt from the book I am trying to write.
The Abrahamic covenant is pivotal to the history biblical which unfolds thereafter, and Genesis 15 is perhaps the key passage to understand with respect to it. The initiative is God’s, and it is here that God binds Himself by oath to perform the details of the promises He makes to Abraham. It will be useful to reproduce the first part of the chapter.
After these things the word of the LORD came to Abram in a vision, saying, “Do not be afraid, Abram. I am your shield, your exceedingly great reward. 2 But Abram said, “Lord GOD, what will You give me, seeing I go childless, and the heir of my house is Eliezer of Damascus?” 3 Then Abram said, “Look, You have given me no offspring; indeed one born in my house is my heir!” 4 And behold, the word of the LORD came to him, saying, “This one shall not be your heir, but one who will come from your own body shall be your heir.” 5 Then He brought him outside and said, “Look now toward heaven, and count the stars if you are able to number them.” And He said to him, “So shall your descendants be.” 6 And he believed in the LORD, and He accounted it to him for righteousness. 7 Then He said to him, “I am the LORD, who brought you out of Ur of the Chaldeans, to give you this land to inherit it.” – Genesis 15:1-7
Sometime after the blessing from the priest of God Yahweh Himself appears to Abram and reiterates His word of promise. The interchange is instructive. Abram’s immediate response to the vision of God is to ask about a child (cf. 11:30). If the land was going to go to his descendants (zera – “seed”) as God had said (13:15-16), then something needed to happen about Sarai’s condition. As every Bible reader knows, God was to do something about that – eventually! But Abram has been brooding on the promise. And he and his wife would certainly have been sensitive on the matter in any case. He is quite forward with God. There is an air of desperation and even irony in his words; “what will you give me, seeing I go childless…You have given me no seed.”
Little did he know that many more years were to pass by until God finally came through. At a time when all hope seemed lost, God showed He was as good as His word. This ought to remind the reader that God will perform exactly what He has said He will do in regard to Abraham’s descendants (national Israel in the context – 15:13) although it appears to many that their time is passed.
The Lord’s reply reassures Abram that his original expectation based on God’s promise (12:2a), was accurate. “This one shall not be your heir, but one who will come from your own body shall be your heir.” (15:4). And yet, every reader of the Bible knows that his trial of waiting for a son was far from over. But Abram did believe what God said to him, not only about an heir, but also about his descendants. Faith in God’s promise is faith in His character, and God’s character can only be trusted if His words can be trusted. Abram’s faith in the promise glorified God and God’s response was to justify Abram as righteous before Him.
The context is very clear that the content of the declaration by God concerning the stars of the heaven and the sand on the seashore evoked trust in Abram and that God reckoned that trust as righteousness to Abram’s account. Abram was not presented with a message about a crucified and risen Messiah. He wouldn’t have known what crucifixion was in any case. When the Apostle uses Genesis 15:6 in his argument for justification he repeats the content of the message while observing the response of God to Abram’s faith (Rom. 4:3-5; Gal. 3:6-7). The onus for Paul is on the faith in God, not on what Abram believed.
Upon the heels of this faith/righteousness transaction the very next thing that comes up is the gift of the land (15:7). For the writer of Genesis, as in the Old Testament generally, the seed and the land belong together. They ought not to be separated in our theology. It is to the subject of the land that the chapter now turns.