I discipline my body and keep it under control, lest after preaching to others I myself should be disqualified (1 Corinthians 9:27). Paul, writing to the church at Corinth to correct their problems, confesses that he himself has to be careful to avoid sin. In fact Paul intimates he goes to great lengths — disciplining his body, keeping himself under control — to avoid the pitfalls of willful sin. But why? Did Paul not believe in the perseverance of the saints, or in the eternal security of believers?
No one who abides in him keeps on sinning; no one who keeps on sinning has either seen him or known him (1 John 3:6). This is a sobering passage. It is meant to be. However, it should not be a passage that causes the Christian believer to despair. John is not condemning the one who is seeking to overcome sin, but the one who habitually gives into sin without repenting. John purposefully describes here the one who is (or is not) continually sinning (as is evident from the “linear present”, or continuing action, of the verbs in the original