Is involuntary omission of a sin in Confession a sin?

I recently read a post concerning absolution of mortal sins that were involuntarily omitted but later remembered. My understanding is that absolution occurs regardless of whether you forgot to confess a mortal sin. However, someone posted the following, which isn’t expressly stated in the standard Code of Canon Law or in the CCC, but does appear in Code of Canon Law, Annotated:

“. . . the penitent continues to be bound to the divine precept of integral and individual confession of sins, just as he or she is under the obligation to confess those sins that, owing to involuntary omission, have not been directly pardoned by the keys of the Church.” [Code of Canon Law Annotated (Latin Rite). Montreal: Wilson & Lafleur Limitee, 1993. Page 625]

If one fails to fulfill this obligation, is this considered another grave matter and possibly another mortal sin? Does it affect the prior absolution? What if someone believes they have confessed everything at one time or another but doesn’t remember specifically having done so?


P.S. It seems that having editions of such documents in varying degrees of completeness or with various degrees of interpretation makes our obligations difficult to know. Any suggestions on how to reconcile this dilemma?

Dear B,

In order to sin seriously, here are those three old friends of ours. It is required that:

  1. the object of the sin is grave matter,
  2. the act was committed with FULL KNOWLEDGE,
  3. and it had our DELIBERATE CONSENT.
    (Catechism # 1857)

You can’t sin without intending to sin. If you forget or are unaware: no sin!

There is NO dilemma!

Fr. Vincent Serpa, O.P.

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