What about "sinless perfection?"
People have always wondered about the Bible verses that appear to teach something like "sinless perfection." Rather than write too much, I have chosen a key verse and written something that I hope is clear enough to help.
In Romans 6:7, Paul wrote "...for he who has died is freed from sin." What does this mean?
Simple answer. You are no longer its slave. It is still there trying to control you, but you don't have to obey it anymore. As you give Jesus your attention, sin will begin to lose is ability to overpower your will and you will find your self-control getting stronger. Then as you begin to say "not my will, but yours," you will acquire more ability to do his will, even when it is not what you feel like doing.
Follow-up: "So what is sinless perfection?"
Simple answer: An illusion. 1 John 1:8 says that "If we say that we have no sin, we are deceiving ourselves and the truth is not in us. " Victory over sin is day by day, and is the same thing as daily cross-bearing. It will always be one step at a time.
Follow-up 2: "Then what is a mature Christian?"
Simple answer: A "fruit bearing" Disciple of Jesus. There are two kinds of "fruit." The presence of Jesus' Spirit in our lives produces in us what Paul calls the "Fruits of the Spirit." He lists them in Galatians 5:22-,23: "...the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness,23 gentleness, self-control..." The other kind of fruit refers to success in making disciples. That is, when you help others learn to follow Jesus through daily cross bearing, prayer, Bible study, fellowship, etc.