Can we focus on this aspect a bit more? I think there's a lot of confusion about this (covenants).
IMO....what complicates it is that there's something radically new happening at Christ's first advent....but also a continuity of what's been foretold in the Old Testament. Christ fulfilled the promises to Abraham, the promises to King David, and the promises to the Israelites. He fulfilled the covenants that humans severed.
The Abrahamic Covenant and the promise to King David are not like the Covenant of Law, in that they are not dependent upon the people's obedience to the Law, and the Abrahamic covenant and the promise to king David pertain to Christ.
1. Abrahamic Covenant: God would be God to the seed of Abraham forever, would give them the land promised Abraham as their everlasting inheritance, and all families of the earth would be blessed through Abraham's seed.
It was unilaterally made with Abraham and His seed by God. It pertains to and belongs to Christ, the seed of Abraham through whom all the families of the earth are blessed ( Galatians 3:16 )
2. Davidic Covenant in whch God swore by oath to king David,
"Once I have sworn by My holiness that I will not lie to David. His seed shall endure forever, and his throne as the sun before Me. It shall be established forever like the moon, and like a faithful witness in the heavens. Selah." Psalm 89:35-37.
It pertains to Christ and is also not dependent upon the obedience of the people for the promised blessings to be obtained.
3. Mosaic Covenant (Covenant of Law): was equally dependent upon the people's adherence to their promise in order for the blessings to be obtained, as it was to God's promise, and was therefore considered God's marriage-covenant with Israel: It promised blessing if the people obeyed, and curses if the people did not obey all that was written in the Law. It was ratified with blood
""And Moses took half of the blood, and put it in basins, and half of the blood he sprinkled on the altar. And he took the book of the covenant, and read in the ears of the people. And they said,
All that the LORD has said we will do, and be obedient. And Moses took the blood and sprinkled it on the people, and said,
Behold the blood of the covenant, which the LORD has made with you concerning all these words." Exodus 24:6-8
But the people were continuously disobedient and continuously broke the covenant, so a new covenant was promised which would not be like it:
"Behold, the days come, says the LORD, that I will cut a new covenant with the house of Israel, and with the house of Judah,
not according to the covenant that I cut with their fathers in the day I took them by the hand to bring them out of the land of Egypt; which covenant of Mine they broke, although I was a husband to them, says the LORD;" Jeremiah 31:31-32)
So just as the covenant of Law was ratified by blood, the new covenant was ratified in Christ's blood when He shed His blood for the forgiveness of sins.
Hence we have two covenants based entirely upon God's oath, and two that are ratified by blood. The first of the two ratified by blood required the obedience of the people, the second was made eternal by the obedience of Christ, the Son of God, who is also the son of Man, the last Adam, who represents all mankind before God.
That's also why after Jesus said He did not come to abolish the law but to
fulfill it, He did what He said - He
fulfilled it, and so the Law
was abolished in His flesh. He was fulfilling the Law in the most complete way while He was dying on the cross, bearing our sins in His own body:
No one has greater love than this, that a man lay down his life for his friends. John 15:13
Jesus said that all the Law and the prophets hung on the commandments to love God with all our heart, mind, soul and strength, and to love our neighbor as ourselves - then He fulfilled the entire Law, abolishing it in His flesh:
Then He said,
I give you a new commandment, that you love one another. As I have loved you, you should also love one another. Jon 13:34
This is why John said,
By this we have known the love of God, because He laid down His life for us. And we ought to lay down our lives for the brothers. 1 John 3:16
This is also why Paul said,
Owe no one anything, except to love one another; for he who loves another has fulfilled the law. For: "Do not commit adultery; do not murder; do not steal; do not bear false witness; do not lust;" and if there is any other commandment, it is summed up in this word, "You shall love your neighbor as yourself."
Love works no ill to its neighbor, therefore love is the fulfilling of the law. Romans 13:8-10
The Abrahamic Covenant pertains to Christ, and so does the promise to king David:
And to Abraham and to his Seed the promises were spoken. It does not say, And to seeds, as of many; but as of one, "And to your Seed," which is Christ. Galatians 3:16
The only seed of Abraham through whom all the families of the earth are blessed, is Christ. He fulfills everything - the covenants and the promises - and He does this as the son of Man, the last Adam, representing all those who are found in Him through faith in Him and in His works.
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