THE TWO COVENANTS
Our Bible is clearly divided into two parts, the Old Testament and the New Testament. Another word for testament is "covenant", so we can say that the OT is based on the "Old Covenant of Law", while the NT is based on the "New Covenant of Grace". Under the Old Covenant of Law, man's obedience to the law was the basis for man to enter into life, and fellowship with God. Several scriptures point this out, such as (Lev 18:5, Ezek 20:11, 13, Rom 10:5, Gal 3:12). However we know that since the fall of Adam, man has no ability to obey God because of our inherited sinful nature. In spite of what some modern psychologists and theologians would tell us, we know from scripture that humanity is inherently sinful and unable to become genuinely acceptable to God be trying to keep certain laws. (Eph 2:1-10). Many other scriptures say more or less the same thing like (Gal 6:14-15, Isa 53:6, Isa 64:6-7, Rom 3:9-12, 1 Peter 4:3, Rom 8:7-8, Mark 7:21-23).
Even though our old sinful human nature, inherited from Adam was crucified with Christ on the cross, the scripture makes it plain that we still have a "flesh nature" that will be with us as long as we live in these earthly bodies. And this flesh wars constantly against the Holy Spirit in the life of a follower of Jesus. However God has provided a way to have victory in this area of our spiritual life. Read carefully (Gal 5:16-26) and see how wonderfully God has provided for us!
Another passage of scripture that bears on this truth is found in Paul's letter to the Romans. In chapter 6, he makes it clear that our old sinful nature died with Christ on the cross, yet in chapter 7, Paul is very honest in his description of how the flesh nature works in his life, to try and keep him from doing the known will of God. We can all relate to his testimony, but praise God Paul goes on in chapter 8 to elaborate on the way to victory through our Lord Jesus Christ! This is really a description of the "New Covenant of Grace", as opposed to the "Old Covenant of Law".
With the introduction of this New Covenant through Christ, man is now able to make the transition from the Old Covenant of law, to this new relationship with God under Grace. Some Christians have taken this truth beyond what God intended, and live their lives as if God doesn't still have rules by which we must conduct ourselves in this new Kingdom life! This will require another study to consider the importance of a correct understanding of God's Grace in our lives.