Jenny asked:

A Christian friend of mine asked if something is a sin, why is there a distinction between mortal and venial?

Karl Keating replied:

"... Let's look at first John 5:17 that tells us not all sin is mortal. The word mortal means deadly ... Human bodies are mortal, it dies ... Mortal sin doesn't mean sin that kills the body, it means sin that kills the soul. In what way, by killing of sanctifying or habitual grace. ... that's the life-giving grace in the soulthat we need to have in our soul when we die if we're going to go to heaven. If we don't have that in our soul when we die we'll take the down escalator.

So some sins are not as serious as others, and some are more serious. Mortal sin concerns something that is grave matter. The subject of the sin is serious. It's committed by the person knowing that it is grave matter, and with full consent. Now if you have any of those things missing, any of those three components missing, the sin is only venial. That is a light thing for example if you steal a nickel from somebody that's not gonna be a serious sin. If you steal a poor person's entire wealth, whatever that is, that's a serious sin because you're doing that person a grave harm.

If you do something without full knowledge that is sinful, you know it's wrong but you're not clear on how serious it is then if you do it it's still for you a venial sin and if you do something only half-heartedly or without full consent again even though the subject matter might be serious you wouldn't incur full guilt about that because you don't have full consent.

So we have mortal sins which are deadly to the life of grace in the soul and venial sins which don't kill off that grace completely but wound it. Consider it like a flesh wound. If you get enough of those you're going to be able to more likely fall into a habit of going into mortal sins. So the bible itself in first John tells us that there are mortal sins and non-mortal sins. So right there we know. It doesn't list for us which sins come under each category, but it does tell us that we have two kinds of sin ..."

Source material:

1 John 5:16-17 16 If any one sees his brother committing what is not a mortal sin, he will ask, and God[b] will give him life for those whose sin is not mortal. There is sin which is mortal; I do not say that one is to pray for that. 17 All wrongdoing is sin, but there is sin which is not mortal.


Revised Standard Version Catholic Edition (RSVCE)
The Revised Standard Version of the Bible: Catholic Edition, copyright © 1965, 1966 the Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.

Catholic Answers, "Open Forum" (San Diego: Catholic Answers, 2014)

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Show air date: July 1, 2014

Name of show: Open Forum

Guest comments by: Karl Keating

Question appeared in show: 17:29

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