But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus Christ, his Son, cleanses us from all sin.

 (ii) He who really knows the truth is daily more and more cleansed from sin by the blood of Jesus. The Revised Standard Version is correct enough here but it can very easily be misunderstood. It runs: "The blood of Jesus his Son cleanses us from all sin." That can be read as a statement of a general principle. But it is a statement of what ought to be happening in the individual life. The meaning is that all the time, day by day, constantly and consistently, the blood of Jesus Christ ought to be carrying out a cleansing process in the life of the individual Christian. 