Note the word ‘testament’ in the ‘Letter to the Hebrews (to Israel)’ as seen in the KJV:

• Hebrews 7:22: “By so much was Jesus made a surety of a better testament.”
• Hebrews 9:15: “And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.”
• Hebrews 9:16: “For where a testament is, there must also of necessity be the Death of The Testator.”
• Hebrews 9:17: “For a testament is of force after men are dead: otherwise it is of no strength at all while the testator liveth.”
• Hebrews 9:18: “Whereupon neither the first testament [the Law] was dedicated without [Christ’s] blood.”
• Hebrews 9:20: “Saying, This [Christ’s blood]is the blood of the testament which God hath enjoined unto you.”

Notice above that the word “testament” is generally used in conjunction with the death of someone. Israel’s New Testament is based upon the death and “shed blood” of “the Lord Jesus Christ” that ‘takes away sins,’ while the earlier O.T. shed blood of sacrificed animals merely ‘covered sins.’ Please reread the verses above as you keep that in mind. Pay close attention to Heb. 9:16-17, noting how a testament is “of force” only After the Death of The Testator. Jesus Christ had to die on the cross before the New Testament could be applied to Israel.

In legal terms, we talk about someone’s “last will and testament.” This is a legally binding document that someone makes in order to manage his or her estate (possessions, et cetera) after their death with regard to their “heirs.” Our KJV Bible is uses the word “testament” in that sense, being most often used in connection with Jesus Christ’s death at Calvary, whereby He then rose from the dead as “the life-giving” “Spirit of life.” (1Cor. 15:45, Rom. 8:2a). Thus, Paul wrote of the members of “the body of Christ”;

“The Spirit itself beareth witness with our spirit, that we are the children of God: ¹⁷And If Children, Then Heirs; HEIRS OF GOD, and JOINT-HEIRS WITH CHRIST; if so be that we suffer with him, that we may be also glorified together. (Rom. 8:16-17)

At Christ’s 2^nd coming God will write His “New Covenant,” laws in each and every believing JEW’S heart (Jer. 31:31-34; Heb. 8:8-13; 10:15-17). Jeremiah 31:31 says the “New Covenant” will be given only to “the house of Israel” and “the house of Judah.” We of “the body of Christ” are NOT Israel and we are NOT under the “New Covenant.” Never does Paul quote Jeremiah 31:31 and apply it to us. The closest passage to Jer. 31:31-34 is what Paul wrote in Rom. 11:27, applying to Israel (cf. verses 25-26). When the writer of Hebrews quoted Jer. 31:31-34 twice, on both occasions, it was a reference to Israel.

So, what did Paul mean saying we are “able ministers of the new testament” 2 Corinthians 3:6? At that time there was a certain religious faction in Corinth that had turned these believers away from Paul’s grace gospel and his apostleship. Note how that throughout this second epistle to Corinth, he had to defend his apostleship (Chapters. 10-13). Paul did not need proof from others to show that he was a legitimate apostle of Jesus Christ. He did not need letters of approval from anyone, even from the Corinthians. He pointed to the Corinthian believers’ abandonment of idols and conversion to the living God as proof of his apostleship. In 2 Cor. chapters 4 and 11 we see that Paul was legitimate apostle of Christ and Paul suffered greatly for the grace Gospel’s sake for all men. During today’s Gentile “dispensation of the Grace of God.” we grace believers are not Israel but “the Church, the Body of Christ.” According to Rom. 6:14-15, we are under grace NOT the law. As we discussed earlier, Israel will ultimately possess God’s laws written IN their hearts (Jer. 33:31-33)

Paul in 2 Cor. 3:1-6 says Christ made us ministers of “the revelation of the mystery” by the Spirit in the hearts of every member of “His body.” The Spirit (cf. 2 Cor. 3:17) writes not on tables of stone and He does not write the “letter [law].” Rather, He writes the truth of Paul’s grace epistles in our hearts. Paul’s grace doctrine working in us unto salvation is proof of Paul’s ministry. God has written His words, the message of His grace, in us. Paul goes on to say that “we have this treasure in earthen vessels, that the excellency of the power may be ‘Of God,’ and not of us.” (2Cor 4:7) This “treasure in earthen vessels” is the “life of Jesus made manifest in our body” (verse 10), it is Him who is living in and through our bodies as we walk by faith in Pauline truth.

By God’s sufficiency, through His Word to us, by power of the Holy Spirit, we are now able to proclaim the benefits of Jesus Christ’s crosswork. We are not under any covenants of any kind during “the dispensation of the Grace of God.” We’re simply recipients of God’s grace, enjoying what He wanted to give us, apart from any promise. We today are enjoying that grace that God will give national Israel one day. Through faith in Jesus Christ’s death, burial, and resurrection we have received the forgiveness of sins (Rom. 5:11). National Israel has to wait for until His 2^nd coming to receive that grace and forgiveness through their “New Covenant” (Zech. 12:10; Acts 3:19-21; Rom. 11:27).

In short; the Law condemns us as sinners and yet Christ’s finished crosswork saves us by making us saints.

1) According to Rom. 3:19-20, the Mosaic Law (the Old Covenant) wasn’t made with us Gentiles, yet it still affected us because it’s moral standards condemn ALL mankind as sinners.

2) Equally, the “New Covenant” isn’t made with us, yet it still affects us in the sense that we rely upon Christ’s underlying crosswork for salvation and to get to heaven (Eph. 2:13).

So, because of the Adamic sin nature we are condemned before God, but, because of Jesus Christ, we can be declared righteousness before God… without any “covenant.”

So, while “covenant” and “testament” are the same Greek word, ‘diathēkē,’ the KJV uses the word “testament” to stress a special type of unilateral promise on God’s part.

• Jesus’ “new testament” refers to an inheritance that requires His “shed blood,” making it enforce “After The Death of The Testator [Jesus]” (Heb. 9:16).
• By contrast, a “covenant” is in force while the maker[s] are living.

This is why our KJV uses “testament” instead of “covenant” in 2Cor 3:6 and other places. It has to do with the riches of Israel’s and our inheritance. All our blessing are now, and based upon the shed blood of Christ.

“In whom also we have [already] obtained an inheritance, being predestinated according to the purpose of him who worketh all things after the counsel of his own will:
¹⁴ Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory. ¹⁸ The eyes of your understanding being enlightened; that ye may know what is the hope of his calling, and what the riches of the glory of HIS INHERITANCE [NOW] IN THE SAINTS,” Eph. 1:11, 14, 18, (KJV)

The grace-age Gentile believers of “body of Christ” today are not under any New Covenant as Israel IS, yet … we do enjoy the same Cross-based blessing of the “New Testament” of “the spirit” that “giveth life” (2Cor. 3:6). Similar to the Jeremiah 33 31-33 promise of God to Israel’s believing remnant, we already have His INDWELLING LIFE with “the law of the Spirit of life” IN our inward parts, and IN our hearts.

In 2 Cor 3:1-6 Paul is saying we of “the body of Christ” are now ministers of the new testament’s message of “reconciliation” to all men of all races, saved and lost, in light of Jesus Christ’s Death at Calvary.

“Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ's stead, be ye reconciled to God.” 2 Corinthians 5:20 (KJV) 

Our “sufficiency is of God,” and so, we are “able” (equipped) to be “ministers of the new testament.” God the Father has committed unto us today “the word of reconciliation,” the message of how God has “reconciled” the world unto Himself by the Cross of Jesus Christ (Read 2 Cor. 5:18-20). All men can now be made right in God’s sight by simple faith in Calvary’s crosswork (2 Cor. 5:21). This is all done by the working of the Holy Spirit. He works in us to bring others the grace Gospel, and He works in them that they might see the grace Gospel by “the Spirit” that “giveth life.”