Mortal Sin and Sacrilege - Full knowledge

I have a doubt concerning the full knowledge recquirement in order for a sin to be mortal. My understanding is that it is enough that you know the act is a sin, that is, you don’t have to be aware that the sin consist of grave matter. Am I right?
Another thing I don’t know for sure is if to commit sacrilege when receiving the Holy Communion one must be aware of his state of mortal sin or even if one receives without “noticing” his state of mortal sin he/she would be stil commiting a sacrilege if receving communion.
Thanks in advance for your answers.

No, the three requirements are…

  1. Grave Matter
  2. Full knowledge
  3. Full consent

This is why mortal sin is the total turning away from God. One must knowingly and willingly commit a sin of grave matter for it to be mortal. If someone didn’t know it was a grave sin, then how could it be a total turning away from God? Full knowledge includes the knowledge that it is of grave matter.
And objectively I think sacrilege is sacrilege. However, a person would be less culpable for the sin of sacrilege if he/she did not know that he/she committed it. It would probably be venial sin. This is why I think people should go to confession more often instead of once a year.
“For he that eateth and drinketh unworthily, eateth and drinketh judgement to himself, not discerning the body of the Lord” (1 Corinthians 11:29, Douay-Rheims).

First, I’d like to compliment you for your concern
esp. about sacrilege.
Offences against the Altar is so COMMON, that
is why the Church is sick and weak(1 Cor 11:30)
Also, it PREVENTS God from working thru His
people! In the Eucharist, we have healing, consecration,
deliverance and power.(Mal 4:2-3).

If one receives in a state of mortal sin, it is a sacrilege, period. To what extent the person would be *culpable *for this sacrilege would depend on his knowledge of his state and its consequences.

OK. Thanks you all for your answers.

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