Mortal sin and venial sin

I was talking to my brother (who is southern Baptist) about religious matters. I mentioned mortal and venial sin and he said that he thinks there’s only one kind of sin. Can someone explain in detail what is venial and mortal sin and where do we get the separation from?

Mortal sin comes straight out of scripture, even though many “bible Christians” refuse to believe it.

Here is the scripture, including two different translations (with the NIV, being a popular version among protestants):

1 John 5:16-17
Revised Standard Version Catholic Edition (RSVCE)

16 If any one sees his brother committing what is not a mortal sin, he will ask, and God[a] 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.

1 John 5:16-17
New International Version (NIV)

16 If you see any brother or sister commit a sin that does not lead to death, you should pray and God will give them life. I refer to those whose sin does not lead to death. There is a sin that leads to death. I am not saying that you should pray about that. 17 All wrongdoing is sin, and there is sin that does not lead to death.

You can read more about the Catholic understanding /teaching here:

The Catholuc Church defines mortal sin as sins that are so very serious that they totally break our relationshio with God. We lose the sanctifying grace necessary for eternal life.
In addition, to commit mortal sin one must know the act is seriously sinful, they myst know that the Church teaches that it is a mortal sin, and they must consciously consent to do it regardless of this knowledge. (If one commits a grave sin, but without full knowledge or consent, then this is a venial sin).

Venial sins are harmful to our relationship, but they do not completely reject God. This makes logical sense. We would all believe that some sins are worse than others. Generally, we would find murder to be more serious than cursing for instance.

1858 Grave matter is specified by the Ten Commandments, corresponding to the answer of Jesus to the rich young man: "Do not kill, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and your mother."132 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.

All sin can be forgiven. Venial sins can be firgiven within one’s own heart and mind by confessing it directly to God. However, to be forgiven for mortal sin, one must go to the sacrament of revonciliation. This should be done as soon as possible to avoid the possibility of dieing with mirtal sin on our soul. If we should die without sacramental grace we will be subject to Hell. Once we have received confession, our full communion with God resumes.

Read here for more specific information:

Is there anything else?

If he believes in “once saved always saved” then he may not even think that sin is important since he is already saved. This also explains why Baptists don’t believe that baptism is necessary because baptism washes away sin. But they are saved when they take Jesus as their personal Lord and savior. They may baptize someone, but it is only because it is an ordinance, that is, Jesus requested it to be done. They may also baptize someone when they want to make them a member of a local church. But it is just a ceremony and doesn’t have any connection to sin.

The reason they pray for sinners is primarily for those who have not yet accepted Jesus. But once that person has accepted Jesus, then their prayers stop for them since they are now saved once and for all. They might pray for other good things, but not over sin.

So to explain mortal and venial sin really doesn’t mean anything to them as they are saved and sin can’t touch them whether mortal or venial. If I believed in that I wouldn’t be interested either.

To reach them on this, it seems to me that the real meaning of baptism needs to be explained, that of water washing a person clean of all sin and saving them, but that it doesn’t mean they can’t lose their cleanliness and holiness by sin. And not every sin will take away their holiness, but just serious/mortal sin, and that is why it is called mortal sin and not venial sin.

Now there are verses in the bible that refer to mortal sin, one verse in particular refers to it by name. There are other verses that St. Paul wrote which state that if a person does these sins, such as adultery, murder, etc., they will not enter the kingdom of heaven. Which right there is saying that “once saved always saved” is a false hope. He says this in several different verses.

And so we catholics have a way of forgiveness if we commit serious sins after baptism which is in agreement of what the bible teaches.

Now you may not experience any reaction if you explain these things to him, but then that isn’t your responsibility but the Holy Spirit’s. You plant the seed, an idea, and let the Holy Spirit bring it to goodness.

May God bless and keep you. May God’s face shine on you. May God be kind to you and give you peace.

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