DISTINCTION BETWEEN THE TWO COVENANTS
Let’s patiently examine the following scriptures: 2 Corinthians 3:6-12 clearly teaches that we have a clear distinction between the two covenants.
1. The OT is called the ministry of death where as the the NT is referred to as the
ministry of life. The Letter(OT) kills!!
2. The OT is called the ministry of Condemnation where as the the NT is referred
to as the ministry of Righteousness
3. The OT is called the ministry of the flesh where as the the NT is referred to as
the ministry of the spirit
The Old Testament is DONE AWAY WITH! Hebrews 8:6-13. Again the Old Testament is referred to as expired! The New made the first old and outdated! When we seek to merge both we end up confused in our worship of God, and general attitude to the faith
A FEW SALIENT FACTS:
1. The Old is the shadow, the New is the substance
Hebrews 10:1 KJV  For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect. Colossians 2:16-17 KJV  Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the Sabbath days :  Which are a shadow of things to come; but the body is of Christ.
2. The Old justified no ONE( Acts 13:38-39).
Justification is only by the New Covenant(refer also to 2 Cor. 3 above and Galatians 3:10-14 KJV  For as many as are of the works of the law are under the curse: for it is written, Cursed is every one that continueth not in all things which are written in the book of the law to do them.  But that no man is justified by the law in the sight of God, it is evident: for, The just shall live by faith .
 And the law is not of faith: but, The man that doeth them shall live in them.  Christ hath redeemed us from the curse of the law, being made a curse for us: for it is written, Cursed is every one that hangeth on a tree: [ 14] That the blessing of Abraham might come on the Gentiles through Jesus Christ; that we might receive the promise of the Spirit through faith.
3. The Old Testament was for ISRAEL and the New Testament is for ALL NATIONS of the world (Including Israel). Seen this? A born-again Christian is a product of the NEW COVENANT in the blood of Jesus, not the Old covenant of the blood of bulls and animals. I function with the reality and not in types and shadows! We should be thankful for the new covenant!
The following are three examples of how the OT can creep up on Christians: 1. Sitting in a Christian meeting where the 10 Commandments or some of the laws in the OT are read and you are told this is what you have to do to be blessed or accepted by God. 2. Feeling guilty or condemned that you don’t do enough for God or that you don’t
go to church or pray or read the Bible enough.
3.Feeling that God doesn’t hear your prayers because you have sinned in some way. To be born-again/ saved means God taking up residence in man, to dwell in man permanently in the person of the Holy Spirit. This was only possible after the resurrection of Jesus (after the cross). This was not possible under OT. People like Adam, Noah, Elijah Moses, Abraham Isaiah etc., none of them were saved because the Holy Spirit was not living in them permanently.
You may as well say, they were given faith, holiness, righteousness on credit which credit was settled in the resurrection of Jesus. Think about why they went to paradise after death NOT heaven!! Paradise was in the heart of the earth not heaven. But right now it is empty!!
Matthew 12:40 For as Jonas was three days and three nights in the whale's belly; so shall the Son of man be three days and three nights in the heart of the earth.Ephesians 4:9 (Now that he ascended, what is it but that he also descended first into the lower parts of the earth? The lower parts of the earth or the heart of the earth is called Hades. Hades has two compartments: Paradise(The temporary place of comfort where Abraham. Lazarus and other OT saints were kept before the resurrection of Jesus) and Hell( the temporary place of torment where the rich man went and unrepentant sinners go).
Today the paradise part of Hades is empty because Jesus rose with OT saints and took them to heaven; however people who reject Jesus still go to Hell part of Hades even today, awaiting the white throne judgement. Then after face the second death in the lake of fire that burns with sulfur.
Someone asked "Why do people still circumcise today since Christ did away with circumcision (an old testament practice)?"
Answer: Circumcision today is purely cultural and for health purpose, for those who chose to do it for their children. Remember all sorts of people decide to circumcise today, NOT just Christians or Jews. Even some atheists circumcise as well. It simply has no spiritual benefits.
The only circumcision that counts now is the Spiritual Circumcision, and that is WHO WE ARE as believers. NOT what we try to do. It is our identity IN CHRIST.
Philippians 3:3 'For WE ARE THE CIRCUMCISION, who worship by the Spirit of God and glory in Christ Jesus and put no confidence in the flesh"
We must stay abreast with the realities concerning two covenants-THE OLD AND NEW COVENANTS. Oftentimes we think it’s a series. Series one is the old covenant, series two the new. Hence in our imaginations we assume they are complements or even supplements. How our imaginations have failed us. The old is thus called because it is OUTDATED AND EXPIRED.
Jesus warned about putting new wine in old wineskins Mark 2:21-22 KJV  No man also seweth a piece of new cloth on an old garment: else the new piece that filled it up taketh away from the old, and the rent is made worse.  And no man putteth new wine into old bottles: else the new wine doth burst the bottles, and the wine is spilled, and the bottles will be marred: but new wine must be put into new bottles. How we have done this too often. We often practice both covenants side by side! We must quickly know it's an error. These two covenants aren't the same. One has REPLACED the other. Thus everything has changed, from culture, relationships, worship, service, prayer etc.! Attempting to mix an expired practice with a new one will give a bad product. Yet this is the norm today in many churches!