During the Sacrament of Reconciliation, the penitent makes an act of contrition, and the wording of many acts of contrition includes a statement of resolve to “avoid all sin”. But how can we poor fallen sinners tell God that we will avoid all sin, when we know that this is nearly impossible?
The Council of Trent infallibly teaches that we cannot avoid all sin:
CANON XXIII — lf anyone says that a person, once justified, is not able to sin any more, nor to lose grace, and therefore he who falls and sins was never truly justified; or, on the contrary, that he is able, in all of life, to avoid all sins, even [those that are] venial — except by a special privilege from God, as the Church holds in the case of the blessed Virgin: let him be anathema.
The Blessed Virgin Mary was conceived without original sin, and she never committed any personal sins. In addition, I hold the pious opinion that Saint Joseph and Saint John the Baptist also never committed any personal sins, though they were each conceived with original sin. Some of the holier Saints may have been able to continue without any sin for periods of time, even though their lives were not entirely free from all venial sin.
But for the common faithful of the Church, it is not possible to avoid all sin. The Council of Trent calls venial sins “light and daily”. The faithful believing and practicing Catholic typically sins daily, by at least venial sins.
So how can we pray to God expressing a resolve to avoid all sin, as found in many acts of contrition?
1. The expression “avoid all sin” indicates, first and foremost, the rejection of sin itself, which is always at least implicit in the love of God and neighbor. For all sin is contrary to that true love. In principle, we fallen sinners, who are also faithful disciples of Christ, reject all sin.
2. Then, too, the expression “avoid all sin” and the principle of rejecting sin itself are primarily a rejection of mortal sin. For venial sins do not separate the sinner from God by depriving the soul of the state of grace — which is the state of loving God and neighbor. And while we poor fallen sinners cannot avoid all venial sins, we certainly can avoid all actual mortal sins. So the resolve to avoid all mortal sins is an achievable goal.
But even if the believing and practicing Catholic falls again to mortal sin, sometime after making a good Confession, he or she can return to Confession and receive forgiveness again. For the mercy of God is infinite. God always forgives repentant sinners.
3. And though we cannot avoid all venial sins, we nevertheless are justified in stating a resolve “to avoid all sin” because the faithful penitent should be willing to strive to avoid venial sins, as much as possible.
A sinner who has in mind only to avoid mortal sins, and who commits venial sins without restraint or remorse, will quickly fall into mortal sins. For he or she is dancing on the edge of the cliff which separates venial sins from mortal sins.
Thus, the confessional resolve to avoid all sin is a faithful and reasonable expression, properly understood.
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