Forgotten mortal sins

how necessary is it to confess forgotten mortal sins that have already been forgiven by previous good confessions? If one remembers a mortal sin from years past, but has since been to confession many times, is it necessary to confess this sin. Will not confessing it result in a bad confession? thank you for your help.

Jesus knows our hearts, and he will know if you truely forgot or if you knowingly omited a mortal sin during confession.
Next time you go to confession, mention to the priest that you truely forgot to mention a past mortal sin. You can also say at the end of your act of contrition, Father, please forgive me for any past sins that I have failed to mention.:wink:

Nick, Kayla is right trust in the mercy of Our Lord. It is necessary however to confess mortals sins that we may have forgotten in the sacrament of reconciliation. Jesus knows our memories aren’t perfect and even our understanding and appreciation of the gravity of sin is often times wanting for lack of proper formation in the faith. Put your mind at rest and simply state to the priest the nature of the sin and how many times. It is not necessary to go into a lot of detail: suffice to say for example, I was a heavy drinker for twenty years, abused and was unfaithful to my wife for thirty. The last ten years I skipped Mass on Sundays.

Also, keep in mind, one must have full knowledge it is a mortal sin and consented to it anyway. That is why while objectively it may be a mortal sin, subjectively due to mitigating circumstances it may not qualify. Nevertheless, all sin offends God and if it is troubling you find peace in the healing powers of the Lord who alone sees and knows our hearts better than we do.

“From the Catechism of the Council of Trent” pg 289

But should the confession seem defective, either becuase the penitent forgot some grievous sins, or because, although intent on confessing all his sins, he did not examine the recesses of his conscience with sufficient accuracy, he is not bound to repeat his confession. It will be sufficient, when he recollects the sins which he had forgotten, to confess them to a priest on a future occasion.
It should be noted, however, that we are not to examine our consciences with careless indifference , or to be so negligent in recalling our sins as to seem as if unwilling to remember them. Should this have been the cse, the confession must by all means be made over again.

In my opinion, if you remember a particular sin that you have not confessed, it is always best to confess it - just to be sure that you receive the penance to make reparation for that particular sin…it is good practice to confess venial sins (faults) too, but we are not obliged to.

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