ASK FATHER: Must I confess mortal sins which I honestly forgot in previous confession?

From a reader…


After a valid confession, if we later remember a forgotten mortal sin, are we strictly obligated to mention it in our next confession, or is it optional? I have found contradictory answers by both priests and laypeople online. Some say you CAN, but it’s not required. Some say you MUST, otherwise it’s a mortal sin and amounts to the same thing as concealing it. So which is it?

First, let’s be clear about something.

If you honestly forgot, or didn’t remember something, but you did your best at the time of the confession, then all your mortal sins are forgiven, even those which were forgotten or not remembered at the time.  However, if you deliberately exclude confessing a mortal sin that you do know about at the time, the absolution is not effective and you have compounded your deliberate omission with the sin of sacrilege, which must now also be confessed.

MUST we confess sins which we had forgotten?  After all, they’ve been forgiven already, right?

Let’s start with a couple of quotes.

CCC 1456:

All mortal sins of which penitents after a diligent self-examination are conscious must be recounted by them in confession…”

You have not yet “recounted” all mortal sins.  Your next confession is your chance to do that.

And  1983 Code of Canon Law 988 §1:

“A member of the Christian faithful is obliged to confess in kind and in number all grave sins committed after baptism and not yet directly remitted through the keys of the Church nor acknowledged in individual confession, of which one is conscious after diligent examination of conscience.”

The key word here is “directly”.

Sins that are confessed have been absolved directly.  Forgotten sins have been forgiven indirectly.

You have not yet had those forgotten or newly remembered sins forgiven directly.

Hence you are obliged to confess them too.

Bottom line, yes, you are obliged to confess those newly remembered mortal sins, in kind and number.

However… remember that remembering the sin does not put you back into the state of mortal sin again by the fact of remembering it.

Even if you have just walked out of church after having made your confession to the best of your ability and – BAM! – you remember something – you are not strictly obliged to turn around and go back into the church and start over.  You can but you need not at that very moment.  You should confess those remembered sins in a future confession, which should be regular and/or as frequent as needed.

It really helps to make a daily examination of conscience and make that examen a part of your routine, such that over a period of time, you don’t have these lapses very often or at all.  Some people have better memories than others.  However, that examination can really help you be thorough and, this is important, far more self-aware.  “Know thyself!”, the ancients cried!  Perhaps one of the wisest bits of advice ever given.


About Fr. John Zuhlsdorf

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  1. Bosco says:

    I am nearly 70 now, Father, and I have a similar concern in respect of confession of mortal sins though not identical.

    As I more intensely examine my past life, I recall any number of sins, serious ones, but cannot remember if I’d ever confessed them. For example, I did X when I was in my 20s. Did I mention it in confession? Can’t recall.

    For the greater part of my life I have availed of confession both frequently and regularly.

    My past life is as though a great cargo ship is now slowly breaking-apart at sea and every now and then some of the debris washes up on the shores and jogs my memory but not sufficiently to recall if I’d been shriven.

    I’ve had a General Confession twice in the past 4 years but still the wash of memories floats in on the tide and worries me.

    Shall I jettison these late-in-life scruples?

  2. Bosco:

    Shall I jettison these late-in-life scruples?

    If they are truly just “scruples” then go ahead and jettison them. If you truly don’t recall if you confessed some past sin or not, it does no harm to confess it. Do, please, avoid rambling. Father and the waiting line thank you in advance.

    You say you have made a General Confession a couple times. Good for you. Keep examining your conscience, but, please, don’t torment yourself. You seem to be diligent and doing your best in your confessions. Remember that when you do your best ALL your sins are forgiven. ALL of them. You do not relapse back into sin when you remember something that you may or may not have confessed a long time ago.

  3. Julia_Augusta says:

    Thank you for writing this post. I had exactly the same question.

  4. Ron Van Wegen says:

    Father, is failing to confess a remembered mortal sin which has been forgiven indirectly a mortal sin? I think the answer must be, “Yes” otherwise it is a venial sin and one is not obliged to confess venial sins. Is this correct?

    [I don’t know what “forgotten indirectly” means.]

  5. I remember what I was taught to say when I was in the second grade (in 1962), to conclude one’s admission of sins:

    “For these and all the sins of my past life, I am truly sorry.”

    It appears to be acceptable to most confessors in my experience.

  6. Ron Van Wegen says:

    Father, can I ask you to revisit my comment/question? I wrote “forgiven indirectly” but you appear to have read that as “forgotten indirectly”. I know you are busy!

    Copied and Pasted from my original comment:
    Father, is failing to confess a remembered mortal sin which has been forgiven indirectly a mortal sin? I think the answer must be, “Yes” otherwise it is a venial sin and one is not obliged to confess venial sins. Is this correct?

    Your comment:
    [I don’t know what “forgotten indirectly” means.]

  7. Mary Fran says:

    Thank you, thank you, thank you, Father Z, for responding to Bosco. This very same thing has troubled me several times in the past. And I am at that point again today. I am 70 and cannot remember whether or not I have confessed some sins in the past—40 years ago or more. I have a hard time remembering what I did or said last week, much less 40 years ago. I have never deliberately omitted any mortal sin. These past sins come to my mind unexpectedly, giving me such torment and I am left panicky with terror that if I die today, I will go to hell. You have given me great peace of mind that all of these have been forgiven and that I have not been racking up more and more mortal sins by going to communion so many times since then. But, I AM going to confession in the morning just to get them off my mind. We Catholics are so blessed to be able to hear the words, “I absolve you from your sins in the name of the Father and of the Son and of the Holy Spirit.” I don’t know how protestants deal with sin and with no assurance that they have been forgiven.

  8. Cornelius says:

    There’s lots of room for falling into scrupulosity in this area.

    [Far far less if you understand it properly. Hence, the question and the answer.]

  9. Patrick L. says:

    Bosco, thank you for your question. I found it very helpful.

Comments are closed.