Confession Required?


If I am understanding correctly, Catholics believe that mortal sins must be confessed to a Priest, or you will not go to heaven? Please correct me if I am wrong, and I apologize if I am.

However, if this is correct, then I have two questions:

  1. Where either in scripture or in early Church traditions can we see that this was the widespread belief?

  2. How, from the same sources, do we know that there is a difference between venial and mortal sins and how do we know where that line is drawn?

Sorry for such simple questions. I’ve been extremely eager to learn as much as I can as quickly as I can, but some of the more complicated theology can be very hard to understand if you aren’t positive about the basic beliefs.

Thank You all for your patience!!


As Catholics, we believe that Jesus Christ instituted the confession of sins for absolution. There are different Bible verses that this is found in, most notably John 20:21-23: “Jesus said to them again, ‘Peace be with you. As the Father has sent me, even so I am sending you.’ And when he had said this, he breathed on them and said to them, ‘Receive the Holy Spirit. If you forgive the sins of anyone, they are forgiven; if you withhold forgiveness from anyone, it is withheld.’”

It’s important to note that in confession, the sinner is confessing to Jesus Christ, for whom the priest is a visible ambassador: “Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ’s stead, be ye reconciled to God.” (2Co 5:20). The Greek word for “ambassador,” is presbeuo, which comes from the root word presbuteros, which is where we get the English word “priest” from. We say that the priest, as ambassador, hears sins in “the person of Christ,” as St. Paul said of himself: “To whom ye forgive any thing, I forgive also: for if I forgave any thing, to whom I forgave it, for your sakes forgave I it in the person of Christ;” (2Co 2:10). Christ forgives the sins through His ambassador, the priest, but it is Christ who is forgiving.

Here is a piece I wrote which goes over these various Biblical evidences more thoroughly:

Here is something to start with for early Church teaching:


In the book of Genesis we read all about the fall of Adam and Eve and about Cain killing Able. While God knew exactly what had happened and what sins had been committed, God still asks Adam and Eve [see Gen 3:11-14] what they had done. Again, when Cain kills Able in Gen 4:10, God asks Cain “What have you done?” God wants us to confess and it is therefore necessary for us to do so.
So where does the priest fit in? **

In Leviticus 5:5-6 we have a solid prefiguring/foreshadowing of confession and this is carried over into the New Covenant. In Lev. 5:5-6 it says, “When a man is guilty in any of these, he shall confess the sin he has committed, and he shall bring his guilt offering to the Lord for the sin which he has committed, a female from the flock, a lamb or a goat, for a sin offering; and the priest shall make atonement for him for his sin.” Note how the penitent must confess and take his sin offering to the priest, and the priest shall make atonement for him for his sin. This requires knowledge of the sin on the part of the priest.

In the New Testament we have a number of verses that refer to the authority to forgive sins. In Matthew 9:6-8, we read “But that you may know that the Son of man has authority on earth to forgive sins”–he then said to the paralytic --“Rise, take up your bed and go home.” And he rose and went home. When the crowds saw it, they were afraid, and they glorified God, who had given such authority to MEN." Notice how scripture says that such authority had been given to men. This is significant and is not merely a coincidence. This is the inspired word of God.

The question of authority and power to forgive sin is given obviously to Jesus and this is further affirmed in Matthew 28:18 where we are told, "And Jesus came and said to them, “All authority in heaven and on earth has been given to me.”

So just how is this authority transfered to the apostles and their successors? In John 20:21-23 "Jesus said to them, “Peace be with you. As the Father has sent me, even so I send you.” ( the authority that was given to him in Mt 28:18 is given to the apostles) And when he had said this, he breathed on them, and said to them, “Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained.” This is an incredible set of verses. They are rich in meaning and power. Notice that Jesus sends the apostles in the same way that the Father sent Him. The Father sent Jesus with all power and authority which included the power to forgive sins. So also Jesus sends the apostles. Jesus breathes on the apostles and says, “receive the Holy Spirit.” There is only one other time in all of scripture where God breathes on man, and that is in Genesis when God breathes life into Adam. This is a significant moment in the upper room and it is at this moment that Jesus says, “If you forgive the sins of any, they are forgiven: if you retain the sins of any they are retained.”

How can men forgive sins if no one is confessing to them? And how can they forgive or retain if no one is confessing to them?

And in context to the Jewish community of that day they knew full well that it was God who forgives sin (Is 43:25) But they also knew God founded a priesthood and threw the priesthood they made atonement for the people. Well Jesus is God and He too just as He did in the Old Testament founded a priesthood given them the authority to forgive sins. This would have been no surprise to the apostles who were Jews.

Later in the new testament scriptures we find additional verses that speak to confession and reconciliation. The most significant are the following:

2 Corinthians 5: 17-20
Therefore, if any one is in Christ, he is a new creation; the old has passed away, behold, the new has come. All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation. So we are ambassadors for Christ, God making his appeal through us. We beseech you on behalf of Christ, be reconciled to God.

regarding sin being deadly or not

In 1 Jn 5:16-17, it says, “If anyone sees his brother sinning, if the sin is not deadly, he should pray to God and he will give him life. This is only for those whose sin is not deadly. There is such a thing as deadly sin; I do not say that one should pray about that. All wrongdoing is sin, but there is sin that is not deadly.”

Catholics have a name for these sins, mortal and venial. This verse clearly points out that all sin is not equal

To know if the sin is deadly well the 10 commandments

Jesus said keep the commandments to enter life

also (Rom 2:8) "but wrath and fury to those who **selfishly disobey **the truth and obey wickedness.

It has alot to do with where your heart is and if you are selfishly disobeying God

hope this helps


Thanks for all the information!

There’s a lot to look at here and no better time to get started than now :slight_smile:


As you’ve seen from others already,
*]some sin can be prayed about and God will give that person life becaue these sins are not deadly… Catholics call these venial sins
*]some sins are deadly (mortal) and these are not to be prayed about.[/LIST]This comes from (emphasis mine)

1 Jn 5:16-17 if the sin is not deadly (venial), he should pray to God and he will give him life. This is only for those whose sin is not deadly(venial). There is such a thing as deadly (mortal) sin; I do not say that one should pray about that (mortal sins)*. All wrongdoing is sin, but there is sin that is (venial) not deadly (mortal).*

You probably ask where is a list of deadly sins in scripture? As a rule, any sin that can keep you from heaven is the deadly (mortal) variety.

Gal 5: 19-21

The acts of the sinful nature are obvious:
*]sexual immorality,
*]impurity and debauchery;
*]idolatry and witchcraft;
*]hatred, discord, jealousy,
*]fits of rage, selfish ambition,
*]dissensions, factions,
*]envy; drunkenness, orgies,[/LIST]I warn you, as I did before, that those who live like this will not inherit the kingdom of God.

1 Cor 6: 9-10

Neither the
*]sexually immoral nor idolaters nor adulterers
*]nor male prostitutes nor homosexual offenders
*]nor thieves nor the greedy nor drunkards nor slanderers nor swindlers[/LIST]will inherit the kingdom of God

Eph 5:5

No immoral, impure or greedy person—such a man is an idolater—has any inheritance in the kingdom of Christ and of God.

Heb 10:25-27 (deliberately missing sacrifice of the Mass on Sunday)

Let us not give up meeting together, as some are in the habit of doing, but let us encourage one another—and all the more as you see the Day approaching. If we deliberately keep on sinning after we have received the knowledge of the truth, no sacrifice for sins is left, but only a fearful expectation of judgment and of raging fire that will consume the enemies of God

Confessing to a priest has already been given.

Every sin can be forgiven in sacramental confession. It’s under the umbrella of forgive and retain. It presumes one confesses to a confessor, otherwise how would a confessor know what to forgive and what to retain as Jesus specified?


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