Therefore, having these promises, beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.
The promises we have is God’s word. God’s word is eternal and He is faithful to fulfill His word. Our relationship with the Lord is based upon a covenant through the shed blood of Jesus Christ. But simply placing our faith and trust in Jesus Christ we are born again and are adopted into God’s family becoming His child. We are able to draw near because of the blood of Jesus Christ.
As believers in Christ we should have nothing to do with the lust of the flesh or the deeds of darkness. To claim to be in Christ, yet walk in the darkness of this world is a deception. A relationship with Jesus is not possible without repentance. Repentance means that we change our heart and our attitude toward the things of the flesh. So it is impossible to claim that we have repented if we continue in sin.
Now does this mean we are going to be perfect or not make mistakes, the answer to that is inevitably no. We make mistakes because we are human. There is no one who is perfect except for Jesus Christ when He walked the earth. Our Father in Heaven desires us to learn from our mistakes and keep growing and maturing. As we mature the mistakes of yesterday are no longer made and we simply focus on growing in Christ on a daily basis.