Forgetting a mortal sin


I posted a question about this in the spirituality section but no one there could give a straight answer. Last Saturday I went to confession and was sorry for the mortal sins I knew I had committed, I received the Eucharist Saturday Evening and Sunday Morning. However yesterday and today I remembered to incidents of possible detraction and I am wondering was I forgiven or did I commit a sacrilege by receiving the Eucharist. I truly didn’t remember the sin. I am going to confess it Saturday but How should I explain it to the priest?
Thank you


Forgotten mortal sins are forgiven in an otherwise valid confession, so you are fine.

Forgotten mortal sins do, however, need to be raised in your next confession. Just say you forgot to mention these in your last confession, and continue as per normal.

That said, “possible detraction” sounds doubtful as to being a mortal sin. But just mention it on Saturday and you will be fine either way.


If you intended to confess all mortal sins, but accidentally forgot one, your confession is worthy and you are absolved of all sins (even the one you forgot). If you give a worthy confession, which it sounds like you did, you did not commit sacrilege when you received the Eucharist. You are not in a state of mortal sin for the accidental omission. However, even though you have been forgiven for the sin you forgot, you are still obligated under canon law to confess the remembered mortal sin at your next confession. I think the obligation arises not out of the need for forgiveness (for the sin truly was forgiven at absolution of the first confession) but out of your need for proper penance. At any rate, I know the obligation to confess the sin is necessary. It would be a new sin if you were to deliberately omit this sin at the next confession.


First incendent more then likely was detraction but I didn’t put it on my list and simply forgot, second one is more iffy is it detraction to say someone watches tv all the time if its true ?


Disregard this , I am going to trust that i forgot them and confess them Saturday as i am sorry and try to do better. Pray for me


It is still forgiven anyway you have no need to go. Just sat father I forgot to confess this sin last time. The priest will say something similar to what I just said


Truth isn’t the issue with detraction, but I will note a few things:

Firstly, detraction is not always grave matter. As with other sins that can be grave matter, they can also be merely venial, when the harm done to the other may be minimal.

Secondly, if someone watches TV a lot and others know this, then you can hardly be guilty of detraction for saying so. It is only detraction to reveal a fault that is not known to the third party.

Thirdly, there can be good reasons for revealing others faults anyway. It is only detraction when there is no just reason to reveal such a fault. We must err on the side of caution of course, but there can be very good reason for revealing faults such as watching too much TV, for it can be an unhealthy habit.

Of course, discussing such issues with our confessors can help us understand better.


If you honestly forgot a mortal sin, that will not invalidate the Confession, but you do need to confess it at your next Confession.


Forgotten mortal sins yes need to be mentioned in next confession.


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