In the Bible, there were a number of covenants made, The most spoken of are the Old Covenant and the New Covenant: “For if that first covenant had been faultless, then should no place have been sought for the second. . . . 10In that he saith, a new covenant, he hath made the first old. Now that which decayeth and waxeth old is ready to vanish away.” Hebrews 8:7, 10
The Old Covenant was not the Ten Commandments but that it was an agreement between the Lord and His people. “For finding fault with them. . . .” Hebrews 8:8, a New Covenant was made under which God’s grace replaced our weakness.
In the Old Covenant God promised He would bless Israel if they obeyed Him (Exodus 19:5, 6). The Ten Commandments were the basis of the covenant. The people relied on their own strength instead of divine strength to accomplish this: “All that the Lord hath spoken we will do.” Exodus 19:8. Here lies the weakness of the Old Covenant in that it was dependent on the promises of people.
The Old Covenant was faulty because man was unwilling to depend on divine help to keep God’s law. Man wanted to rely on his own strength. “For finding fault with them, he saith, Behold the days come, saith the Lord, when I will make a New Covenant with the house of Israel and with the house of Judah . . . 10For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts; And I will be to them a God, and they shall be to me a people.” Hebrews 8: 8, 10.
In the new and better covenant that Christ has fulfilled the law for us, if they receive Him by faith as a personal Saviour. "As many as received him, to them gave he power to become the sons of God." John 1:12. Mercy and forgiveness are the reward of all who come to Christ trusting in His merits to take away their sins. In the better covenant we are cleansed from sin by the blood of Christ.
Then by faith the grace of God renews the heart, and brings it into harmony with the principles of His law. In the New Covenant it is not the works of the flesh, but “Christ in you, the hope of glory.” Colossians 1:27.
The Old Covenant was by works, sacrifices, and ordinances. By faith, the New Covenant is in the promises of God yet the Ten Commandments are still the basis of the covenant. Like the Old Covenant in the New Covenant, the conditions of eternal life are perfect obedience. “Do we then make void the law through faith? God forbid: yea, we establish the law.” Romans 3:31.
The New Covenant does not change God’s law but it equips us with power to obey it through the sacrifice of the life of God’s only begotten Son for Christ is the “Lamb slain from the foundation of the world.” Revelation 13:8. This tells us that the New Covenant - the grace provided for through the death of Christ - existed before the Old Covenant because it was here from the foundation of the world. The Book of Hebrews confirms that Abraham believed in the New Covenant by faith.
There is no salvation in an Old Covenant experience (righteousness by works). It is only through the New Covenant experience of faith in Jesus (righteousness by faith) that we have salvation.
If we accept Jesus to come live in our hearts, His will reign in our lives. And thus the our life will be a continual submission so that “not my will, but thine, be done.” Luke 22:42
For more information and Bible verses on this vital subject, pleae read: The Two Covenants.

