Is it a mortal sin to sin on purpose

for example say you know its a sin to text and drive will that be a mortal sin, or you know its a sin to cuss or sell things at school and still do it will it be a mortal sin?

By definition to sin means to do it on purpose. If one does something accidently or without knowing it is a sin, then no sin was committed.

There are three things that are needed for a sin to be committed:

  1. The matter, or what you are doing,the act itself. Grave matter is required for a mortal sin.
  2. Knowledge that what you are doing is sinful.
  3. Consent to do the act.

I would not be able to tell you whether the examples that you give above would be mortal or not without more details, although texting and driving might be close bacause of the risk being taken.

There are no “accidental” mortal sins. One cannot sin outside of one’s free will. One must knowingly and willingly choose to sin. Otherwise, one is not culpable.

Ask your spiritual advisor. Or your priest in confession. It would have to be grave matter, and there are many circumstances to consider.

All mortal sins are on purpose, but not all purposely committed sins are mortal. If the object itself is not grave matter, even if you intentionally committed it, it will be venial. Purposely stealing a dollar from a millionaire is not grave matter and is therefore not mortal sin.

It is because my friend wants to buy a game from me and wants to buy it off of me from school will it be a mortal sin to sell that game to him at school purposely im selling the ps3 game to him for like $10 bucks. Would this be grave matter

How is selling a game a sin? :confused:

See: (Sin/Capital/Venial)

How is this in any way a sin? Unless you don’t actually own the game cartridge you are attempting to sell? If you do own the game, and your school has rules against selling personal goods on school time or on school property, wait until after school and leave school grounds before transacting the deal.

Taken from a very reputable book from the 19th century called The Way of Interior Peace by Fr. Lehen, pg. 99:

“To a mortal sin belong three points: 1st. Weighty matter; – a jesting lie, for example or a vain, self-conceited thought, is not sufficient for a mortal sin. 2d. Full knowledge of the evil; that is, the deliberate consciousness that what one does is a mortal sin. This excludes all cases in which the sin proceeds from surprise, or in which the soul is not full master of her powers; as, for example, in half-slumber, and the like. 3d. Full consent of the will to that which the understanding knows to be mortal sin. As long as the consent remains imperfect, or we are conscious of a certain hesitancy, a deferring, or a reproach of conscience in consequence of our neglect in combating the temptation, the sin is only venial.”

I hope this helps.

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