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.
What promises? In the previous verses Paul tells that we have received the same promises that Israel had when God promised to dwell with them when they separated from the unclean and he would be their Father. In our salvation we have become the temple of God and with that comes a need to treat that temple with reverence and respect for the one who dwells there. When we come face to face with the reality that we have a holy God we will become more aware of our unholiness, much like Isaiah did when he was transported into the throne room of God (Isa. 6). So Paul says, now that we have come to recognize that we are God’s temple and we have the promise of his presence as a Father, then your response to our holy Father is to cleanse ourselves of those activities that defile the temple. When he was speaking to the Colossians Paul says, “Put to death therefore what is earthly in you.” That is to say, kill it, murder it. As we become more aware of our sin because the grace of God is revealing those things to us our response should be one of holy fear because we have a holy God and therefore we rid ourselves of those things that we in turn may be more holy. But we can’t do that by our own strength or power, we can only do that by looking to Christ (Col. 3:1-3).