Every Covenant has its own blessings and obligations. Moses' covenant enacted at Sinai contains stipulations of blessings and cursings (Deuteronomy 28). Failure to comply to the Terms and Conditions bring on the penalties in the forms of "curses": "Tell them that this is what the Lord, the God of Israel, says: 'Cursed is the man who does not obey the terms of this covenant — the terms I commanded your forefathers when I brought them out of Egypt, out of the iron-smelting furnace.' I said, 'Obey me and do everything I command you, and you will be my people, and I will be your God. Then I will fulfill the oath I swore to your forefathers, to give them a land flowing with milk and honey' — the land you possess today" (Jer 11:3-5). But we know that Israel and Judah continually violated the terms and conditions of the Covenant and the penalty kicked it, leading to the ultimate curse -- expulsion from the land of "flowing with milk and honey."
The New Covenant has its own terms and conditions too. Jesus' covenant enacted at Golgotha, the place of His crucifixion, is entered by faith and kept through obedience: "make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you" (Matt 28:19-20). The goal of the covenant is an obedient people, who is committed to God's vision and value. Under the Old Covenant, Israel was chosen to be God's people on the basis of God's promise to their forefathers Abraham, Isaac and Jacob. In some sense, they had no choice about being God's "Chosen People". In the New Covenant, we enter freely by a choice we make: to follow Christ (become His disciples). The basis to be New Covenant people is to put our faith in Christ. When we have done that, the promise of the Spirit is given to us and we become empowered by the Spirit to walk in obedience: "Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins. And you will receive the gift of the Holy Spirit (Acts 2:38).
No longer can New Covenant people say, "We have no choice. We couldn't help it." New Covenant people choose to enter the Kingdom freely by faith and as a result receive the power to obey, viz., the Holy Spirit. New Covenant believers can no longer say "we can't help it" because God's infinite power in the Person of His Holy Spirit now indwells every believer. We can only say, "We don't want to help it." In contrast, Old Covenant people didn't have the Holy Spirit indwelling as a permanent and personal gift, So, they failed because they had to keep the terms and conditions based on their own power. But though their covenant was inferior, so were their obligations. In contrast, New Covenant people has a superior covenant, but our obligations are higher (see Matthew 5:20-48).
Under the Old Covenant, murder is killing someone; under the New Covenant, murder is anger against someone. Under the Old Covenant, adultery is sleeping with someone not your spouse; under the New Covenant, adultery is looking lustfully at someone not your spouse; under the Old Covenant, we are obligated to love our neighbours; under the New Covenant, we are obligated to love our enemies. Under Old Covenant, our measure of moral perfection is the Law; under the New Covenant, our measure of moral perfection is the Lord: "Be perfect, therefore, as your heavenly Father is perfect" (Mt 5:48). Jesus and the Father are one; and therefore, Jesus becomes our standard and goal of our moral perfection.
Even for people under the New Covenant, the call to imitate the human Christ may yet fall on deaf ears. Nevertheless, this is the Apostle Peter's clear exhortation in 1 Peter 2:21-23, "To this you were called, because Christ suffered for you, leaving you an example, that you should follow in his steps. He committed no sin, and no deceit was found in his mouth. When they hurled their insults at him, he did not retaliate; when he suffered, he made no threats. Instead, he entrusted himself to him who judges justly." The human Christ is our model of perfection, not the heavenly Christ. We can remake the heavenly Christ in our image because no one has seen him. But we can't remake the earthly Christ because His life and conduct is recorded in the Gospels for all to read. The Gospels were not written in order to be phased out by Paul's epistles. The Gospels were written to reveal the human Christ as our ultimate Model of Perfect Humanity. We must always measure ourselves against that image of Christ, not something else we have created in our own mind.
Father, we thank You that You have given us a New Covenant with New Blessings and New Obligations. May You make us more like Jesus in His humanity, so that we might become like Him, the true sons and daughters of God. Amen.