The characteristic of the Pharisees under the Old Covenant was summed up by what Jesus said: “Do as they say, not as they do” (Matthew 23:3). Under the New Covenant, however, we are instructed to pay close attention to our life (first) and (then) to our teaching (I Timothy 4:16). And the standard for our life on earth must always be the life of Jesus, because that is what it means to be a Christian (I John 2:6).
We can have such a life despite the fact that we have all sinned in the past because of the completeness of (a) God’s forgiveness through Jesus’ death and (b) God’s justification through Jesus’ resurrection (Romans 4:25). While we walk as Jesus walked, if we stumble, the blood of Jesus Christ cleanses us from all sin (I John 1:7-9). If we WALK as Jesus walked faithfully until the end of our lives, when we see Him we will BE like Him (I John 3:2-3) — we will have His nature fully.