We're running a two-for-one special here at About Catholicism. For this week's Reader Question, we have two related questions from two unrelated readers.
Reader "fleetjames" writes:
I'm awaiting completion of my conversion to Catholicism, and I am wondering about the difference between, and definitions of, venial and mortal sin.
Meanwhile, Paul Dale asks:
What is the difference between the Act of Reconciliation in the Mass and with a priest? Can you confess a mortal sin at Mass and be forgiven, or do you need to see a priest? Am I correct in saying that you must not go to Communion until you have confessed a mortal sin?
These are both excellent questions, and sadly far too many Catholics today are confused about the answers. Priests who stress the importance of Confession have often noted that almost everyone receives Communion at Mass on Sunday, but very few people go to Confession the day before. That could mean that those priests have remarkably holy congregations, but it's more likely that many (perhaps even most) Catholics today think of the Sacrament of Confession as either optional or even unnecessary.
Nothing could be further from the truth. Confession not only restores us to grace when we have sinned but helps to keep us from falling into sin in the first place. We shouldn't go to Confession only when we are conscious of mortal sin, but also when we are trying to uproot venial sins from our lives.
But now we're getting ahead of ourselves. What are venial and mortal sin?
Actual sin, as the venerable Baltimore Catechism defines it, "is any wilful thought, word, deed, or omission contrary to the law of God." That covers an awful lot, from impure thoughts to "little white lies," and from murder to staying silent when a friend of ours spreads gossip about someone else.
Obviously, all of these sins aren't of the same magnitude. We might tell our children a little white lie with the intention of protecting them, while cold-blooded murder can never be committed with the thought of protecting the person killed.
Thus the distinction between the two types of actual sin, venial and mortal. Venial sins are either small sins (say, those little white lies) or sins that normally would be much bigger, but are (as the Baltimore Catechism says) "committed without sufficient reflection or full consent of the will."
Venial sins add up over time—not in the sense that, say, ten venial sins equals a mortal sin, but because any sin makes it easier for us to commit further sins (including mortal sins) in the future. Sin is habit-forming. Lying to our spouse about a small matter may not seem like a big deal, but a series of such lies, left unconfessed, might be the first step toward a greater sin, such as adultery (which, in its essence, is just a much more serious lie).
Mortal sins are distinguished from venial sins by three things: The thought, word, deed, or omission must concern something serious; we must have thought about what we are doing when we commit the sin; and we must consent completely to it.
We might think about this like the difference between manslaughter and murder. If we're driving down the road and someone runs out in front of our car, we obviously have not intended his death nor given our consent to it if we can't stop in time to avoid hitting and killing him. If, however, we are angry at our boss, have fantasies about running him over, and then, given the opportunity to do so, put such a plan into action, that would be murder.
So are mortal sins always big and obvious? Not necessarily. Take pornography, for instance. If we're surfing the web and inadvertently run across a pornographic image, we might pause for a second to look at it. If we then come to our senses, realize we shouldn't be looking at such material, and close the web browser (or better yet, leave the computer), our brief dalliance with pornography may be a venial sin. We hadn't intended to view such an image, and we didn't give the full consent of our will to the act.
If, however, we keep thinking about such images and decide to return to the computer and search for them, we're headed into the domain of mortal sin. And the effect of mortal sin is to remove sanctifying grace—the life of God within us—from our soul. Without sanctifying grace, we cannot enter Heaven, which is why this sin is called mortal.
So what does this mean for our second question? By the "Act of Reconciliation in the Mass," I assume that Mr. Dale is referring to the Penitential Rite ("I confess to Almighty God . . . ") at the beginning of Mass. At the end of the Penitential Rite, the priest offers a general absolution, saying, "May almighty God have mercy on us, forgive us our sins, and bring us to everlasting life."
This absolution, however, can only free us from the guilt of venial sin. (For more on this, see "Reader Question: Reconciliation Services.") If we are conscious of mortal sin, then we must receive the Sacrament of Confession. And Mr. Dale is correct: Until we have done so, we must refrain from receiving Communion.
Indeed, to receive Communion while conscious of having committed a mortal sin is to receive Communion unworthily—which is another mortal sin. As Saint Paul (1 Corinthians 11:27) tells us, "Therefore whosoever shall eat this bread, or drink the chalice of the Lord unworthily, shall be guilty of the body and of the blood of the Lord."