If you have the flew and the doctor prescribes medicine and you forget to take it, does that mean you will get better on your own?
How long has been since the penance was assigned to you. Why didn’t you do the penance right after confession? I think the answer is no it does not make the confession invalid, but you probably did not receive the full benefit of the healing graces God is providing for you. You should do the penance and next time in the confession alert the priest to your forgetfullness and ask for forgiveness.
No, God does not take back what He has given (absolution).
However, if you remember what the penance was, you should still do it. If not, you should probably mention that you neglected to do your penance at your next confession.
If one is truly sorry for their sins, their sins are forgiven regardless if the penance was performed or not. However, whatever penance we fail to perform in this life will be required of us in the next life in purgatory and more than one saint has stated that we can pay our debt in this life with pennies on the dollar compared to what will be expected of us in the next life.
no, not at all, one simply performs the penance when they remember it. If you forget what it was, you can simply perform a penance you have received under similar circumstances, or that your priest usually assigns, or that you choose. In no case is the absolution withdrawn, even if you do nothing.
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