S. Michael Houdmann.
A covenant is an agreement between two parties. There are two types of covenants: conditional and unconditional. A conditional or bilateral covenant is an agreement that is binding on both parties for its fulfillment. Both parties agree to fulfill certain conditions. If either party fails to meet their responsibilities, the covenant is broken and neither party has to fulfill the expectations of the covenant. An unconditional or unilateral covenant is an agreement between two parties, but only one of the two parties has to do something. Nothing is required of the other party.
The Abrahamic Covenant is an unconditional covenant. God made promises to Abraham that required nothing of Abraham. Genesis 15:18-21 describes a part of the Abrahamic Covenant, specifically dealing with the dimensions of the land God promised to Abraham and his descendants.
The actual Abrahamic Covenant is found in Genesis 12:1-3. The ceremony recorded in Genesis 15 indicates the unconditional nature of the covenant. The only time that both parties of a covenant would pass between the pieces of animals was when the fulfillment of the covenant was dependent upon both parties keeping commitments. Concerning the significance of God alone moving between the halves of the animals, it is to be noted that it is a smoking furnace and a flaming torch, representing God, not Abraham, which passed between the pieces. Such an act, it would seem, should be shared by both parties, but in this case it is doubtless to be explained by the fact that the covenant is principally a promise by God. He is the one who binds Himself. God caused a sleep to fall upon Abraham so that he would not be able to pass between the two halves of the animals. Fulfillment of the covenant fell to God alone ….
The Abrahamic Covenant … is an unconditional covenant. There are no conditions attached to it (no “if” clauses, suggesting its fulfillment is dependent on man). It is also a literal covenant in which the promises should be understood literally. The land that is promised should be understood in its literal or normal interpretation — it is not a figure of heaven. It is also an everlasting covenant. The promises that God made to Israel are eternal ….
God’s method of fulfilling the Abrahamic Covenant is literal, inasmuch as God partially fulfilled the covenant in history: God blessed Abraham by giving him the land (Genesis 13:14–17); God blessed him spiritually (Genesis 13:8, 18; 14:22, 23; 21:22); God gave him numerous descendants (Genesis 22:17; 49:3–28). The important element of the Abrahamic Covenant, however, demands a future fulfillment with Messiah’s kingdom rule ….
The Abrahamic Covenant finds its ultimate fulfillment in connection with the return of Messiah to rescue and bless His people Israel. It is through the nation Israel that God promised in Genesis 12:1–3 to bless the nations of the world. That ultimate blessing will issue in the forgiveness of sins and Messiah’s glorious kingdom reign on earth.