Early on in his First Letter, St John warns us that "if we say we have no sin in us, we deceive ourselves" (1:8), yet in today's passage we hear him say, "No one who is begotten of God sins; he cannot sin because he has been begotten by God." It seems that John contradicts himself. But in every case where the Bible seems to contain a contradiction, we must reflect carefully to discover what the author is truly saying.

From an examination of the thought of this whole Letter, we can say that John is using the verb "to sin" in two different ways. We may express these two meanings as "to commit a sin" and to "lead a sinful life". Even though we may sin, that does not necessarily mean that we live a sinful life.

Because we do in fact commit sins now and again, Jesus gave the Church the power to forgive the repentant sinner. True repentance includes a resolution to strive not to sin or not to commit this particular sin in the future. Leading a sinful life is an entirely different matter: it implies continuing to sin with little or no intention of reforming one's life by repentance.