Mortal vs. Venial Sins

siniiJesus exhorts us in Matthew’s Gospel to, “be perfect, just as your heavenly Father is perfect.” Yet Paul tells us in his Epistle to the Romans that “All have sinned and fall short of the glory of God”.

We know that because of original sin we all have the tendency toward sin. And we know that except for Mary (who was conceived without original sin) and for Jesus, all of us are sinners. Yet Jesus tells us we don’t have to continue to sin. At each moment of temptation when Satan lies to us as he did to Adam and Eve – when Satan tries to make sin look “good” – we can choose in that moment to be perfect as our Father is perfect. We can look the devil in the eye and use the words of Saint Benedict, “Be gone Satan! Drink the poison yourself!”

And, for those times we fall for Satan’s lies and fall short of the glory of God, Jesus instituted the sacrament of Reconciliation.


Venial sin damages our relationship with God; mortal sin completely separates us from God. The sacrament of Confession was instituted by Jesus to reconcile us to the love of the Father, which is why it is often referred to as Reconciliation.

The Bible, beginning in Leviticus, commands us to confess our sins. Why does God require us to confess our sins? So He will know what we have done? He certainly already knows our sins. Why then? So that we will have to come face to face with our sins, and hopefully repent and turn back toward God.

We are required to confess serious sin at least once a year – and if we are in the state of mortal sin we must not receive the Eucharist until receiving absolution. The Catechism encourages us to confess venial sin regularly because it “helps us form our conscience, fight against evil tendencies, let ourselves be healed by Christ and progress in the life of the Spirit.”

A good confession begins with a good examination of conscience. Resources to assist with this examination include:

Frequent Confession

We are required to confess serious sin at least once a year – and if we are in the state of mortal sin we must not receive the Eucharist until receiving absolution. So, if we have no mortal sin to confess, does that mean there is no reason to receive the sacrament? No! Quite the opposite.

We are encouraged to confess our sins regularly. Pope Saint John Paul II confessed his sins weekly. Doing so has many spiritual and practical benefits. Spiritual benefits include the forgiveness of our sins and the grace we receive from the sacrament.

From a practical perspective, by regularly examining my thoughts and my words, what I have done and what I have failed to do, and comparing these, not to my neighbor, but to the love of God, I see that I fall short and need reconciliation. Doing this regularly increases my sensitivity to my areas of weakness, and, hopefully lets me see how I need to change my behavior. Lord, give me eyes to see.

Frequent Confession, by Benedict Bauer

Why must I confess to a priest?

The simple answer is because Jesus established the sacrament that way. In John’s Gospel, after Jesus’s resurrection, He says to the apostles, “Peace be with you. As the Father has sent me, so I send you.”  And when he had said this, he breathed on them and said to them, “Receive the Holy Spirit.  Whose sins you forgive are forgiven, and whose sins you retain are retained.” We, then, must confess our sins to the priest in order for him to know which sins to forgive and which to retain.

Remember, the priest in the confessional is acting “in persona Christi”, that is, in the person of Christ. Jesus said in Luke’s Gospel, “In speaking to his disciples, Jesus said, “He who hears you hears me, and he who rejects you rejects me.”  So we are confessing to Jesus through the priest. And it is Jesus who gives us absolution. Thanks be to God!

JN 20:21-23, LK 10:16

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