Faith And Sin

Magna ista quaestio: Omnis qui peccat, non vidit eum, neque cognovit eum. Non est mirum. Non eum vidimus, sed visuri sumus; non eum cognovimus, sed cognituri sumus: credimus in eum quem non cognovimus. An forte ex fide cognovimus, et specie nondum cognovimus? Sed in fide et vidimus et cognovimus. Si enim nondum videt fides, quare dicimur illuminati? Est illuminatio per fidem, est illuminatio per speciem. Modo cum peregrinamur, per fidem ambulamus, non per speciem. Ergo et iustitia nostra per fidem est, non per speciem. Erit perfecta nostra iustitia, cum videbimus per speciem. Modo non relinquamus eam iustitiam quae est ex fide, quoniam iustus ex fide vivit, sicut ait Apostolus. Omnis qui manet in ipso, non peccat. Nam omnis qui peccat, non vidit eum, neque cognovit eum. Non credit iste qui peccat: si autem credit, quantum ad fidem eius pertinet, non peccat. Sanctus Augustinus Hipponensis, In Epistolam Ioannis ad Parthos Tractatus Decem, Tractatus IV Source: Migne PL 35.2010

This is a great question: 'All who sin have not seen Him, nor known Him.' 1 Which is no marvel. We have not seen Him, but we are to see; we have not known Him, but are to know; we believe in Him whom we have not known. Or perhaps it is that by faith we have known, and by sight we have not yet known? But in faith we have both seen and known, for if faith does not yet see, why are we said to have been enlightened? There is an enlightening by faith, and an enlightening by sight. While we are on pilgrimage, 'we walk by faith, not by sight.' 2 Therefore also our righteousness is by faith and not by sight. Our righteousness shall be perfect, when we shall see by sight. Meanwhile, let us not relinquish that righteousness which is of faith, since the righeous man lives by faith, 3 as the Apostle says. 'Whoever abides in Him, does not sin.' 1 For, 'whoever sins, has not seen Him, nor known Him.' He who does not believe, he sins; but if a man believes, so far as pertains to his faith, he does not sin. Saint Augustine of Hippo, from the Fourth Tractate on the First Letter of John 1 1 Jn 2.18 2 2 Cor 5.7 3 Rom 1.17