“For we are the temple of the living God; as God said, “I will make my dwelling among them and walk among them, and I will be their God, and they shall be my people. Therefore go out from their midst, and be separate from them, says the Lord, and touch no unclean thing; then I will welcome you, and I will be a father to you, and you shall be sons and daughters to me, says the Lord Almighty.”
Since we have these promises, beloved, let us cleanse ourselves from every defilement of body and spirit, bringing holiness to completion in the fear of God.”
(2Corinthians 6:16-7:1 ESV)
Paul has shown us that the New Covenant reality has been actualized by the Spirit.
This is seen in the context. Paul claimed in v. 2 that now is the eschatological day of salvation. He spoke of the new creation in 5:17, “If anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come.” This is the gospel reality of the New Covenant. The new creation has broken into the old. We are those upon whom the end of the age has come! Because of the death, burial, and resurrection of Jesus Christ, because He has ascended and sent His Spirit to gather and indwell His church, the realities of the New Covenant are enjoyed in this broken world.
And it upon this that he makes the command in 7:1: “let us cleanse ourselves of every defilement of flesh and spirit.” The every defilement that we are to cleanse ourselves from is anything in our lives that is a contradiction to the reality of the New Covenant! It is all the old stuff, that although it has passed away and the new has come, the old is still there. And we hate it and we just want it to go away.
How do we cleanse ourselves of it? It keeps coming up. Yes. It does and it will. This is the nitty-gritty stuff of sanctification. We go through our hearts and discover those things that contradict the gospel and when we find those things we declare over them the glorious reality of the gospel! The New Covenant is here and it is real. We are dead to sin and alive to God in Christ by the Spirit. This is how we are sanctified. The gospel of Jesus Christ comes to have its fullest effect on our lives. Sin will be no more and we will be perfectly conformed to His image.
And in our experience, we know that this is not something that we ourselves make happen. Sin is still there. This is the tension that makes us groan. We groan inwardly as we wait eagerly for adoption as sons, the redemption of our bodies. We mortify our sin and pray, “Come, Lord Jesus!”