Mortal vs Venial Sin: The Difference, With Examples

A sin is mortal when it gravely breaks the divine law, and venial when it breaks it only slightly. Mortal sin kills the life of the soul, which is sanctifying grace; venial sin wounds that life without destroying it. To commit a mortal sin three things must be present together: grave matter, full knowledge that the act is gravely sinful, and the free consent of the will. Where any one of the three is wanting, the sin is not mortal. This is the constant teaching of the Catechism of St Pius X and the Catechism of the Council of Trent.

Mortal vs venial sin: the difference at a glance

Before we treat each in turn, the short answer. Mortal and venial sin differ in three respects: in the gravity of the matter, in the effect on the soul, and in the way each is pardoned.

	Mortal sin	Venial sin
Matter	grave	slight, or grave matter without full knowledge or consent
Effect on the soul	kills sanctifying grace; the soul loses its supernatural life	wounds charity; the soul keeps the life of grace
Friendship with God	broken; the soul turns away from God	not broken; the soul stumbles on the way to Him
Conditions	grave matter + full knowledge + full consent, all three together	one of the three is wanting, or the matter is light
If one dies in it	the soul is lost	the soul is saved, after purgation
How it is pardoned	must be confessed in kind and number in the Sacrament of Penance	confession, contrition, prayer, the sacraments, works of penance

The rest of this article unfolds each line of this table. The single rule behind it: grave matter alone makes a sin capable of being mortal, but the act becomes mortal in a given soul only when full knowledge and full consent are joined to that grave matter.

What kind of sin we are speaking of

The Church distinguishes first between original sin, which we contract through the disobedience of Adam and which is blotted out by Baptism, and actual sin, which a man commits by his own free will once he has come to the use of reason. The distinction between mortal and venial belongs to this second kind: actual sin is itself of two sorts, mortal sin and venial sin. So when we ask about mortal vs venial sin, we are weighing two ways in which a man, knowing and willing, turns from the law of God.

What is mortal sin

Mortal sin is a disobedience to the divine law by which one gravely fails in one's duties towards God, towards one's neighbour, and towards oneself. It is called mortal, that is, death-dealing, because it gives death to the soul by making it lose sanctifying grace, which is the life of the soul as the soul is the life of the body. The name is exact: a soul in mortal sin is a soul that has lost its life.

The Catechism of St Pius X sets out plainly what mortal sin does. Mortal sin:

• deprives the soul of grace and of the friendship of God;
• makes it lose heaven;
• deprives it of the merits already acquired and renders it incapable of acquiring new ones;
• makes it a slave of the devil;
• makes it deserve hell, and also the chastisements of this life.

This is why a single unrepented mortal sin is enough to separate a man from God. The good works done while in this state earn no reward for heaven so long as the soul remains dead in grace; and the man who dies in mortal sin is lost.

The three conditions for mortal sin

Not every grave act is, in the man who does it, a mortal sin. For a sin to be mortal, three conditions must all be met at once.

1. Grave matter

The thing done, said, or willed must itself be seriously contrary to the law of God. Mortal sin, the catechism says, is that by which one gravely fails in one's duties. A small theft, an idle word, a slight impatience does not, of its own nature, carry this gravity. Murder, blasphemy, adultery, the deliberate refusal of God do. The matter must be grave in itself, not merely felt to be serious.

2. Full knowledge

Besides the gravity of the matter, the Catechism of St Pius X teaches, there is required the knowledge that one is committing the sin. The sinner must know, at the moment he acts, that what he is doing is gravely wrong. A man who acts in genuine, inculpable ignorance of the gravity of his act does not commit a mortal sin, because his will does not knowingly turn from God. This is why the catechism speaks of actual sin only in one who has reached the use of reason: where there is no knowledge, there is no full sin.

3. Full consent of the will

The act must proceed from the free consent of the will. Actual sin is what a man commits by his free will; a movement that the will does not consent to, a temptation suffered and resisted, a fault committed in sleep or under a violence the will does not accept, is not a mortal sin. Sin lives in the consent. The greater the deliberation, the greater the consent, and the heavier the guilt.

Grave matter, full knowledge, free consent: these are the conditions for mortal sin, and all three are required together. Remove any one and the act, however grave its matter, is not a mortal sin in the soul that did it. This is the measure a Catholic uses when he weighs his conscience.

What is venial sin

Venial sin is a slight disobedience to the divine law by which one fails only slightly in some duty towards God, towards one's neighbour, or towards oneself. It is called venial — that is, easily pardoned — for three reasons: because it is slight in comparison with mortal sin, because it does not make us lose sanctifying grace, and because God pardons it easily. The soul in venial sin remains alive in grace; it has not turned away from God, only stumbled on the way to Him.

Venial sin arises in two ways. Either the matter itself is light — a small uncharitable thought, a little vanity, a minor untruth. Or the matter is grave, but one of the other two conditions is lacking: the knowledge was not full, or the consent was not complete. A grave act done in half-awareness, or without the will fully consenting, does not kill the soul; it remains a venial fault.

Why venial sin is no small thing

It would be a very great error to think that, because venial sin is pardoned easily, no account need be made of it. Venial sin always contains a real offence of God, and it does the soul harm grave enough to take seriously. The Catechism of St Pius X names three injuries it works:

• it weakens and cools charity within us;
• it disposes us to mortal sin;
• it renders us deserving of great temporal punishments, in this world or in the next.

The danger is in the second of these. A soul that grows careless with venial sin loses fervour, and the loss of fervour opens the way to the grave fall. Venial faults are not the death of the soul, but they are its sickness, and a sickness left untended prepares the death. The Catechism of the Council of Trent notes, with St Augustine, that even venial sins require their own kind of penance: the daily penance the Church performs for these slight faults would be empty if they could be remitted without it.

Mortal vs venial sin: examples

A few concrete examples make the difference plain. In every case the same rule holds: the matter sets whether a sin can be mortal, but the act becomes mortal in this soul only when full knowledge and full consent are joined to grave matter.

Examples of mortal sins — acts whose matter is grave in itself, set by the Ten Commandments and the precepts of the Church:

• to deny God, to fall into heresy, or to have recourse to the devil and to spiritism (first commandment);
• to blaspheme God, the Blessed Virgin, or the Saints, and to swear a false oath (second commandment);
• to omit Mass on a Sunday or holy day of obligation without grave cause (third commandment);
• to put a man to death, to procure or attempt suicide, or to gravely harm a neighbour's body — and to wound his soul by grave scandal (fifth commandment);
• adultery and every deliberate act, look, or word against chastity (sixth and ninth commandments);
• to steal a thing of importance, or a smaller thing by which the neighbour suffers a grave loss (seventh commandment);
• to ruin a neighbour's good name by grave calumny, detraction, or a pernicious lie that does grave harm (eighth commandment).

Examples of venial sins — sins slight by their matter, which wound charity without killing the life of grace:

• a small uncharitable or vain thought, a movement of impatience or petty anger;
• a slight untruth told in jest or to excuse oneself, where no grave harm is done — the catechism calls the jocose and the officious lie a venial sin;
• the theft of a thing of little value that causes the neighbour no grave loss;
• a minor distraction or coldness in prayer, a little gluttony, an idle word.

The contrast is exact. A grave theft is mortal in its matter; pilfering something trifling is venial. Murder is mortal; a flash of resented anger is venial. Adultery is mortal; a passing vain thought is venial. A lie sworn before God, or one that destroys a man's reputation, is mortal; a small lie told to spare embarrassment is venial. And the bridge runs both ways: a sin of grave matter drops to venial when full knowledge or full consent is wanting, while a sin of slight matter remains of itself venial, however deliberate.

The moralists note only the exceptions that come from outside the act: light matter becomes grave when it is done out of contempt for God's law, when it gives grave scandal, when it serves a gravely evil end, or when an erroneous conscience sincerely judges it grave and acts anyway. This is the whole of mortal vs venial sin, read off the three conditions.

A note on the "list of mortal sins"

People often search for a fixed list of mortal sins, as though gravity could be read off a table. The Church does not work in quite that way. Grave matter is set chiefly by the Ten Commandments and the precepts of the Church — the examples of mortal sins above are drawn straight from them. The seven deadly sins — pride, covetousness, lust, anger, gluttony, envy, and sloth — are the roots from which graver sins grow; a good examination of conscience passes the soul through them after the commandments. But whether a given act is, in this sinner, a mortal sin depends always on the three conditions above. A list names the grave matter; only the matter together with knowledge and consent makes the mortal sin.

How the distinction is used: confession

The distinction is not academic. It governs the confessional. All mortal sins committed after Baptism must be confessed in the Sacrament of Penance, named in their kind and number. This sacrament is the ordinary way back to the state of grace; an act of contrition made from perfect sorrow restores grace sooner only because it already contains the resolve to confess, and the obligation to confess remains. Venial sins may be confessed, and it is good to confess them, but they can also be remitted by other means — by contrition, by prayer, by the worthy reception of the sacraments, by works of penance.

The Council of Trent calls Penance a second plank after the shipwreck of sin: when baptismal innocence is lost, this Sacrament is the means by which the life of the soul is restored, not once only but as often as a man falls and turns back. The power to forgive them was given by Christ to His Apostles on the evening of the Resurrection, in the words we read in John 20:23, "whose sins you shall forgive".

For this reason a careful examination of conscience asks of each fault: was the matter grave, was the knowledge full, was the consent free? On that judgement hangs whether the sin must be confessed as mortal. Our examination of conscience sets out the questions in full, with examples of how a sin is put into words, and what is confession explains the sacrament in which mortal sin is forgiven. The Iter Fidei confession app marks each question of its examination as grave or venial matter and carries a short helper for the cases where you cannot tell. Sorrow need not be perfect to be enough within the sacrament; the distinction is drawn in contrition and attrition.

The heart of the difference

Mortal sin destroys the divine life in the soul; venial sin wounds it. Mortal sin requires grave matter, full knowledge, and full consent, all three together; venial sin is either a slight matter or a grave one without full knowledge or consent. The first must be confessed and absolved before a man can again call himself a friend of God; the second, real and not to be despised, can be wiped away in many ways but should never be carried lightly. To know the difference is to know the state of one's own soul, which is the first thing a Christian must guard.

Frequently Asked Questions

What is a mortal sin in the Catholic Church?

A mortal sin is a grave disobedience to the divine law that kills the life of the soul by making it lose sanctifying grace, the friendship of God, and the right to heaven. The Catechism of St Pius X teaches that it makes the soul a slave of the devil and deserving of hell. It is called mortal — death-dealing — because a soul in mortal sin is a soul that has lost its supernatural life and, if it dies unrepentant, is lost forever.

What is considered a mortal sin in the Catholic Church?

For any sin to be mortal, three conditions must be present together: grave matter, full knowledge that the act is gravely wrong, and the free consent of the will; remove any one and the sin is not mortal. Grave matter is set chiefly by the Ten Commandments and the precepts of the Church — denying God, blasphemy, missing Sunday Mass without grave cause, murder, adultery and every deliberate sin against chastity, grave theft, and ruining a neighbour's good name. The Church gives no fixed checklist, because whether such an act is mortal in this soul depends always on the knowledge and consent joined to that grave matter.

What is venial sin in the Catholic Church?

A venial sin is a slight disobedience to the divine law that wounds the soul's charity without destroying its life of grace. It is called venial — easily pardoned — because it is slight beside mortal sin, does not make us lose sanctifying grace, and is pardoned easily by God. It arises either when the matter itself is light, or when grave matter is done without full knowledge or full consent; though pardoned easily, it cools charity and disposes the soul to mortal sin, so it must never be despised.

Is touching yourself a mortal sin in the Catholic Church?

By its matter, every deliberate sin against the virtue of chastity is grave; the sixth and ninth commandments admit no light matter, and a wilful act of self-abuse is therefore grave matter. Whether it is, in this soul, a mortal sin depends on the other two conditions: full knowledge that the act is gravely wrong, and the free consent of the will. Where grave matter is joined to full knowledge and full consent, the sin is mortal and must be confessed before returning to the state of grace; where consent was not full — a fault of weakness only half-willed — the guilt is lessened, but the matter should still be named in confession when in doubt. We treat the question from Scripture in what God says about masturbation.

Is adultery a mortal sin in the Catholic Church?

Adultery is grave in its matter, forbidden directly by the sixth commandment, and so it is among the clearest examples of mortal sin. Joined to full knowledge and the free consent of the will, it kills the life of grace in the soul and must be confessed in kind and number in the Sacrament of Penance before the sinner can return to the state of grace. The ninth commandment extends the same gravity to the deliberate desire of another's spouse, for our Lord teaches that he who looks to lust has already committed adultery in his heart.

What is the difference between mortal and venial sin?

Mortal sin kills the life of the soul; venial sin only wounds it. Mortal sin requires three conditions together — grave matter, full knowledge that the act is gravely wrong, and the free consent of the will — and it makes the soul lose sanctifying grace, the friendship of God, and the right to heaven. Venial sin is either a slight matter, or a grave matter done without full knowledge or full consent; it cools charity and disposes us to greater falls but does not destroy the life of grace. The first must be confessed in kind and number before a man returns to the state of grace; the second can also be remitted by contrition, prayer, and the sacraments.

What are examples of mortal sin and venial sin?

Examples of mortal sin — acts grave in their matter — include denying God or having recourse to spiritism, blasphemy and false oaths, missing Sunday Mass without grave cause, murder and grave bodily harm, adultery and every deliberate sin against chastity, grave theft, and ruining a neighbour's good name by calumny or detraction. Examples of venial sin — slight by their matter — include a movement of impatience or petty anger, a small uncharitable or vain thought, a jocose or officious lie that does no grave harm, the theft of something trifling, and distraction in prayer. The same act of grave matter drops to venial when full knowledge or full consent is lacking; an act of light matter stays venial, however deliberate, unless contempt, grave scandal or a gravely evil end is joined to it.

Is gossip a mortal sin?

Gossip is not a single thing, and its gravity follows what it does to the neighbour. To ruin a man's good name by grave calumny — a false charge — or by detraction that needlessly makes known a real but hidden grave fault is mortal in its matter, for it robs him of a good he cannot easily recover. Idle talk that does no real harm, or a small uncharitable word, is venial. As with every sin, the matter sets only what the act can be; it becomes mortal in the speaker only when full knowledge and full consent are joined to grave matter, and the harm done binds him to restore the good name he has wounded.

The Iter Fidei app carries a full examination of conscience with each question marked mortal or venial, a helper to weigh the three conditions, and a private notebook to prepare your confession. Join early access here.

Sources. Catechism of St Pius X, Part V, ch. 5 (Sins and Their Principal Kinds); Catechism of the Council of Trent, ch. 21 (On the Sacrament of Penance).