Paul said, “John baptized with the baptism of repentance, telling the people to believe in Him who was coming after him, that is, in Jesus.” (Acts 19:4)
Whenever people bring up the idea that repentance is necessary to become a Christian, that is, part of salvation, for some reason, people say, “Oh, you believe in sinless perfection.” While it seems odd to connect the two, what they mean is that they believe that if repentance has to be part of salvation, they are assuming that you must be able to repent of every sin one by one, reciting a catalogue of every sin you have ever committed. They are misunderstanding the difference between individual sins and the sin nature.
While God clearly commands us to turn from our sins, attempting to make a catalogue or list of every sin we have ever committed is neither possible nor expected according to what is taught in the Word of God.
But the tax collector, standing some distance away, was even unwilling to lift up his eyes to heaven, but was beating his breast, saying, ‘God, be merciful to me, the sinner!’ 14 I tell you, this man went to his house justified rather than the other;
Jesus said that the man was justified by acknowledging his sin, without listing individual sins. To the woman taken in adultery, Jesus said, “I do not condemn you, either. Go. From now on sin no more.” (John 8:11) He healed a man, and Afterward Jesus found him in the temple and said to him, “Behold, you have become well; do not sin anymore, so that nothing worse happens to you.” (John 5:14)
These are all individual acts of repentance. Peter said to them, “Repent, and each of you be baptized in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit. (Acts 2:37) This is a clear teaching of Scripture. It was a major theme of all the major prophets of the Old Testament. It is mentioned repeatedly throughout the New Testament. Nowhere does the New Testament teach that we as believers will attain sinless perfection in this life. Nor do we have to be sinlessly perfect to be saved. What God requires of us is to acknowledge our sin. It is possible to repent of sin without turning to the Lord Jesus Christ. Repentance is not the only thing necessary for salvation, but repentance is necessary for salvation.
Image from http://1Photos.com.