The old covenant which God made with Israel through Moses was contingent on the people obeying the commandments of God. If they obeyed they would receive blessings from God and if they disobeyed, curses. It became apparent that Israel, or for that matter anyone else, was unable to keep all the commandments of God. So now God began to announce through His prophets what He was ultimately planning to do for His people through a new covenant. In other words, the old covenant also served the purpose of convincing people that no one could find acceptance with God on the basis of keeping the commandments because no one could fully keep them.

Under this new covenant, God would do things which the people could not do by themselves, and He would enable the people to do what He wanted them to do. He would take away their stony hearts and give them fleshy hearts, put His Spirit in them, 'write' His laws upon their hearts and minds and cause them to walk in His ways. From the least to the greatest of people, all would be able to know Him personally. God would be compassionate and merciful to their sins, and He would not remember them (bring to remembrance) any more. In other words, it would not be dependent on the people to learn and obey the commandments, but God would do a work inside them so that they will want to obey and they will also receive the power to obey.

It was through the blood of Jesus the Messiah ('the anointed one' in Hebrew, Christ in Greek) that the new covenant was ratified. Now under the new covenant, salvation comes through grace from God, or the undeserved favour He shows upon us. We can receive this salvation freely, as a gift, when we go to God repenting from our past sins, and accepting the death of Jesus as our Substitute dying in our place for our sins. The Jews in the days of the prophets could not understand exactly what the prophets were saying about the Messiah. In the days of Jesus on earth, the Jews thought that the Messiah's work would be to free their nation from the Romans who ruled them. But it is when we know the truth about Jesus and then look back at the preparatory work that God did centuries earlier, that we can begin to get the whole picture.