Steve H. asks about the Abrahamic Covenant:

I know it is often treated as one covenant, but it seems to me to be at least three covenants. They are closely related, but slightly different. The first is Genesis 15:18 and has to do with the descendants of Abram (which would include Ishmael) and the lands named in Gen 15:18-21. The second in Genesis 17 and requires circumcision. That second covenant seems to be more about Abraham being a father of many nations, being exceedingly fruitful, and and have Canaan as an everlasting possession. The third is with Isaac but it is because of Abraham’s faith.  Genesis 17:21 says “…My covenant I will establish with Isaac, …”.  The covenant with Isaac is the one that contains the promise about “…all the nations of the earth shall be blessed, because you have obeyed my voice.” (Gen 22:18).

Let me start by stating that there are two kinds of covenants in the Bible: conditional and unconditional. In conditional covenants, both parties are only bound to it so long as both parties meet the covenant stipulations. As soon as one party fails in their covenant responsibility, the covenant is no longer binding.

In an unconditional covenant, only one party is required to maintain it. The nature of the Abrahamic covenant (Gen 12:1-3) is understood as being unconditional, as seen in the covenant ceremony described in Genesis 15 where only one party (God) passed between the animal pieces.

While there may seem to be different covenants with Abram, there was only one unconditional covenant that consisted of three different parts: land, people, and redemption of the world. In Gen 12:1-3, God promises Abram land. God also promises that Abram will produce a great nation (singular), and finally, God also promises redemption blessings through Abram: His name will be great, he would be a blessing to others, nations would be blessed or cursed depending on their treatment of the people of Abram, and all nations would be blessed through the line of Abram.

Land (Gen 12:1)

The covenant promise of land is given in greater detail in Gen 15:18-21, which lays out the boundaries of this land inheritance. Gen 13:15 says the inheritance is forever. The boundaries of this land is also expanded as an addition to the Abrahamic Covenant in Deut 30:1-10. This expansion is also known as the Palestinian Covenant. Israel has yet to ever possess all of the land of this covenant, and so we are still waiting for that future time when Israel does fully possess this land of promise. full possession of the land brings the fulness of the worship of God and His great redemption (Ezek 20:40-44; 36:1-37:28).

People (Gen 12:2)

The promise of descendants were that they would number “as the dust of the earth” (Gen 13:16), and as the number of the stars and grains of sand (Gen 15:5; 22:17). Many nations would come from Abraham (Gen 17:6), which would include Ishmael and the Arab peoples, yet God stipulates that the Abrahamic Covenant of land, nation (singular), and redemption would only occur through the line of Isaac (Gen 17:21 cf. Gen 21:12-13; Rom 9:6-13) and Jacob (Gen 25:23; 27:40). Although God did promise to make Ishmael great (Gen 21:18), that was the limit of what he received, and he did not inherit any other of the Abrahamic promises—contrary to the claims of Islam. That may sound hard, but Ishmael was the son of the flesh and not the son of God’s promise.

Abraham only saw the miraculous beginning of God’s covenant promises in the birth of Isaac. Even though he was born 25 years after God’s initial promise to Abraham, and even though Abraham would never experience the other promises of God’s covenant with him, he would always be reminded of them and renewed in his faith of God to do the impossible whenever he looked at the stars, the dust, and the sand.

Redemption (Gen 12:3)

This promise finds its fulfillment both in the the New Covenant (Lk 22:20) and when Jesus returns (Jer 31:31-34). This fulfillment happens through Abraham’s Seed (Gal 3:16), who is Jesus. He is the Redeemer who has commanded that disciples be made of all nations (Matt 28:18-20) and who will restore everything (Acts 3:21). One day, the Messiah will return to set up His throne, and through His righteous rule, the whole world will be blessed with an abundance of peace, pleasure, and prosperity.