Mortal Sin, Missing Mass, and Confession: Reader Q&A

Let’s chat mortal sin, missing Mass, and the necessity of confession in this edition of Reader Q&A.

My favorite part of blogging is connecting with readers and I especially love to receive your encouragement, thoughts, and questions in my inbox.

Today we are tackling one reader’s questions covering mortal sin, missing Mass, and the necessity of confession in forgiveness of mortal sin.

why is missing mass a mortal sin and what is mortal sin anyway?

Mortal Sin, Missing Mass, and Confession

Dear Elizabeth,
Would you be able to share your thoughts on missing Sunday Mass or Mass on holydays of obligation as a mortal sin?
Also I’d like to know more about why we need to participate in the sacrament of reconciliation for the absolution of mortal sin?
These topics trouble my evangelical protestant mind but I am trying to be open minded.
Your Reader

These are such great questions and definitely ones that most protestant converts need to wrestle with at some time (myself included).

READ MORE: You can read my own conversion story here.

Let’s break these questions down a bit.

What is mortal sin?

The first thing to understand is what we mean by the term mortal sin.

In Catholic teaching, a sin must fulfill all the following requirements to be considered mortal:

be serious (grave matter)
we freely choose it (full consent)
we understand the gravity of our choice (full knowledge)

If one of those elements is missing, the act is not a mortal sin.

By fulfilling the requirements for mortal sin, we are rejecting God and the grace He has given us.

Such a direct defiance against God’s law results in our loss of God’s life given to us at baptism.

Unfortunately, sin is downplayed in our current world, but scripture clearly demonstrates its seriousness.

Here are a few scriptural examples to illustrate not only the seriousness of sin but how we risk our salvation by choosing sin over God:

“And if your eye causes you to sin, pluck it out; it is better for you to enter the kingdom of God with one eye than with two eyes to be thrown into hell, where their worm does not die, and the fire is not quenched.” Mark 9:47-48
“Now the works of the flesh are plain: immorality, impurity…..envy, drunkenness, carousing, and the like. I warn you, as I warned you before, that those who do such things shall not inherit the kingdom of God.” Gal 5:19-21
“For if we sin deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful prospect of judgment, and a fury of fire which will consume the adversaries.” Heb 10:26-27
“I tell you, on the day of judgment men will render account for every careless word they utter; for by your words you will be justified, and by your words you will be condemned.” Matt 12:36-37

What is venial sin?

Sometimes we make poor choices with little thought, with pressure on us, or maybe we would like to follow God’s truth but don’t fully know His truth – these sins are considered lesser. “Venial” is the official word used in Catholic theology.

Again, our varying culpability (or guilt) when it comes to sin can be found in scripture:

“If I had not done among them the works which no one else did, they would not have sin; but now they have seen and hated both me and my Father.” John 15:24
” …but I received mercy because I had acted ignorantly in unbelief” 1 Timothy 1:13

Despite this, we never want to say, “That’s just a venial sin, so it’s okay.”

While venial sin does not remove God’s life in us, it does wound our relationship with Him, makes our soul sick, and can lead us into mortal sin.

Missing Mass a Mortal Sin?

But how can missing Mass on required days (Sundays and Holydays of Obligation) be a mortal sin?

First, it would have to be a serious matter and that is in fact what Catholics believe.

Jesus’ plan was to give us His Body and Blood in the Eucharist (Holy Communion). Through this plan He gives us the help or grace we need to follow Him.

Through the scriptures and early Church writings, we see that the preeminence of the Eucharist in the life of a Christian was a core belief in the faith of the early Christians.

“When, therefore, the mixed cup and the baked bread receives the Word of God and becomes the Eucharist, the Body of Christ, and from these the substance of our flesh is increased and supported, how can they say that the flesh is not capable of receiving the gift of God, which is eternal life – flesh which is nourished by the Body and the Blood of the Lord…receiving the Word of God, becomes the Eucharist, which is the Body and Blood of Christ…”
Against Heresies 5:2:2-3, St. Irenaeus of Lyons, 2nd Century

Along with this, we believe that in the New Covenant the commandment to keep holy the Lord’s Day is still active but fulfilled by meeting to receive the Eucharist on the Lord’s day.

Sunday Mass is the act that fulfills the Catholic Church’s understanding of Jesus’s commandment from the Last Supper to “Do this in remembrance of Me.”

The Church, with the authority given by Jesus, has the responsibility and ability to command the followers of Jesus according to it’s understanding of Jesus plan and concern for them.

There are many scriptures and early Church Father’s quotes on the authority of the Church, but we will save that discussion for another day.

However, I will give you one short analogy to explain further.

An example illustrating Church authority…

In short, we can relate Church authority a little bit to a child’s relationship to their parent.

Using the family’s fancy dishes for a meal is not inherently sinful, but if a mother, using her authority as a mother, commands her son not to use them, and he chooses to do so any way in defiance, that is now a real sin.

Similarly with Mass, there is no inherent moral law involved. But we understand that Jesus wants us to meet as a Church, and the Church has told us to do so.

If I as a Catholic defy the Church and say, “I know better,” I am disobeying the wishes of Jesus as expressed through the authority He has provided through the Church for my help and guidance.

Whether it is actually a mortal sin is judged by God alone. He is the only one who knows our personal culpability when it comes to full knowledge and full consent – the other two requirements for a sin to be mortal.

Each of us can declare an act a grave matter but we can not judge the knowledge and consent of the person acting.

Through scripture and the Church father’s, I hope you can see that missing Mass is a grave matter.

Mortal sin forgiven only in Confession?

The topic of confession has some similarity in that we once again can turn to the blessing that is the authority of the Catholic Church.

Jesus intended the Church be involved in the reconciliation of persons to Himself when we fall into sin.

He gave the apostles a special charism of the Holy Spirit to forgive the sins of a person on His behalf.

“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.’” John 20:21-23

I might ask,” How would an apostle retain my sin if he didn’t know it?”

In the early Church priests and bishops were very clearly involved in the reconciliation process of someone who committed a serious offense. Today’s bishops and priests are seen as present day descendants of the apostles, still bearing Jesus’s provided authority for the care of his followers.

Confession, as well as the Mass, is intended to be a gift, not a burden, and I can testify to this in my own life.

Not only do we receive God’s forgiveness in the confessional, but we also receive His strengthening grace (supernatural help).

It took me a while to feel comfortable during confession after my conversion, but the graces I receive there always draw me back.

Again, if I as a Catholic say, “‘I’ve sinned, but I’m not going to involve the Church,” that would not be a proper response to my beliefs.

The Church does say that if we have a contrition that is based on loving God above all else (referred to as “perfect contrition”), we can be reconciled with God before we’ve even gone to confession.

“Among the penitent’s acts contrition occupies first place. Contrition is “sorrow of the soul and detestation for the sin committed, together with the resolution not to sin again. When it arises from a love by which God is loved above all else, contrition is called “perfect” (contrition of charity). Such contrition remits venial sins; it also obtains forgiveness of mortal sins if it includes the firm resolution to have recourse to sacramental confession as soon as possible.”
Catechism of the Catholic Church 1451-1452

Of course, we should want to repent in love of God for any sin right away. God is not bound by His sacraments: