I’ve been trying to figure out the difference between mortal sins and venial sins. I’ve read what the Catechism has to say about the matter. But it seems like everything is a mortal sin! I mean if i fight with my parents, i know it’s wrong but it hardly seems like it’s of grave matter. I’m just hoping you can shed a little light on mortal and venial sins. And possibly include a list of possible mortal sins vs venial sins.
Thanks, Mortal Madness

Dear Mortal Madness,

I looked at what the Catechism of the Catholic Church has to say on mortal and venial sin. I confess that I don’t read it that same as you do: “But it seems like everything is a mortal sin!” My parish priest used to give us the formula for a mortal sin. : B+K+W. Big, knowledge, and (full) Will.

It has to be BIG — what you propose to do has to be seriously wrong; it has to violate a serious value. The examples that are given in #1858 of the Catechism: “Do not kill, Do not commit adultery, do no steal, do not bear false witness, do not defraud, honor your father and your mother.” And it goes on “The gravity of sins is more or less great: murder is graver than theft. One must also take into account who is wronged: violence against parents is in itself graver than violence against a stranger.”

I don’t think you are having difficulty with conceiving the gravity of the offense in taking a person’s life or in committing adultery (breaking the marriage bond of pledged fidelity). It is hard to kill just a little bit or to be adulterous a little bit. But probably your difficulty has to do with theft, and lying and honoring father and mother. There can be a sliding scale of graveness (or bigness) in this kind of thing. In our common sense estimation, there is a big difference in stealing $5 worth and $1000. Hard to think of $5 as BIG — serious matter, grave offense. On the other hand it is hard to conceive of $1000 as of little consequence. But even here, stealing $5 from a very poor person or from a person who is well off can change the gravity of the action.

I think we can also speak of ‘little white lies’ as opposed to lies which have serious consequences — like telling lies about someone which tear down his/her character. It is hard to repair the damage we do by the latter kind of lie. And it can be very destructive of the person (and, why would one tell that kind of lie unless one means to tear the other person down). This latter is different even from idle gossip — but even here we have to be careful. Not much good is done in this kind of conversation and it has potential for harm.

As far as honoring or dishonoring one’s parents. What is at stake here in terms of ‘grave matter’ is a habitual attitude and behaviour towards parents — a kind of consistent “I don’t give a damn what you say” approach to them. This is quite different in quality and approach from some of the disagreements and unpleasant exchanges that can arise even when we love our parents and want to show them respect and honor. That is not to condone the latter. but I think parents feel a great difference between the two. The first I would say is serious ‘stuff.’ The second less serious — though it is the stuff of apology, asking and giving forgiveness.

As my parish priest used to say B+K+W. So even if we have established that the offense is serious, the K and W must also come into play in order to commit a mortal sin. As #1857 of the Catechism tells us, for a sin to be mortal, such that it snuffs out the life of grace (union with God) in us, besides there being a serious value that is at stake (Matter) we must have ‘full knowledge’ (K in the formula) and ‘deliberate consent.’ (W part of the formula). Again as the Catechism states #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 (This is what we mean by its gravity, making some of the common sense distinctions which we made above). It also implies a consent sufficienty deliberate to be a personal choice.”

In other words, for a mortal sin to occur, the kind of sin that is totally incompatible with living in the love and grace of God, it requires, besides the serious issue of the act itself, considerable ‘not caring about my life with God, not caring about the harm I do by my taking what belongs to someone else, by my lie about somebody, not caring about how this or that affects my parents. I go ahead with ‘sufficient knowledge’ of what it does and I will to do it anyway (for whatever pleasure or supposed advantage it gives me). That is not to say we should not be concerned about anything less than a mortal sin — about taking the $5 about the ‘little white lies’ — the venial sins in our lives. After all they do tend to sap our spiritual life of its energy. They tend to cloud our vision of the goal of our life’s journey. And is there not something of a slippery slope that we are on?

In general, I would say that, in someone serious about trying to live a good Christian life, trying to be true to one’s own principles, concerned about one’s love for God, and trying to be respectful (and loving) towards one’s neighbour, mortal sin doesn’t just creep up on us. That it constitutes a major detour in one’s life and one is aware of it — and is choosing to go in that direction. It demands true conversion of heart and God’s mercy, — for us Catholics — normally accomplished with the sacrament of reconciliation.

I hope this gives you some sense of what the Church means when it makes the distinction between mortal and venial sin.

aka Fr. Ray C.Ss.R.