Sin is defined by St. Augustine as “Factum vel dictum vel conception aliquid contra legem aeternam” ~ Any Thought, Word, or Deed against the eternal Law of God.
Or to be more concise: Anything not the Will of God.
The Catechism of the Catholic Church states:
1857 For a sin to be mortal, three conditions must together be met: “Mortal sin is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent.”
Or in other words:
- The Sin must be grave in matter. The Ten Commandments are all grave in matter. Also the six precepts of the Church.
- The person must have full knowledge that they are committing the act. They don’t have to know that the matter is grave, only that they are committing it.
- The person must be willing to commit the act. The person can not be forced to act and it still be considered neither willing, nor can the person be considered willing if they are not in there normal frame of mind.
If these three conditions aren’t met then the Sin is Venal.
An exercise I use to give RCIA candidates when I instructed and always lend itself to an evening long discussion was this:
A man is traveling down a street when a child darts out in front of his vehicle and is run over and dies. Was mortal or venal sin committed here?
First of all the class would try and show where this was an accident and not a sin at all. And I would have to point out that from St. Augustine definition of sin that if this wasn’t sin then God would have to have willed that child to die. And there would be those that had a hard time with seeing that there were only two choices; either it was Gods will or it wasn’t. There is no third alternative.
Once the class accepted that a sin was committed then we could move on with whether it was a venal sin or mortal. Then we had to discern if One; it was a grave matter. All of us would ready agree that the killing of a child was grave. Two; For the sake of argument I said that the man saw the child dart out in front of his vehicle. So yes, he knew he was running over the child. Three; Did the man willing run the child over? If the child darted out and the man could see what was happening but had no time to react then, no; the man wasn’t willing and only venal sin had been committed. If all three conditions aren’t met then the sin is venal in nature and not mortal. One of the conditions have to be true for it to be mortal, if one condition is false then the sin is venal.
1859 Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart do not diminish, but rather increase, the voluntary character of a sin.
This paragraph from the Catechism is confusing because it seems to imply that the person needs to know that they are committing a sin which is not the case. A murderer only has to know that they are taking another’s life and be willing to do it for that person to be in mortal sin.
