Aquinas: Some Sins Worse Than Sexual Sins (Updated)

This week, Pope Francis noted that sexual sins or sins of the flesh are not the worst kind of sins during an interview on a plane. There have been three mistaken reactions to this. First, many secular sources assumed he meant these didn’t matter. This is obviously false. Sexual sins are often mortal sins so are serious and can result in someone being unable to go to heaven. Second, some argued all mortal sins are the same. Third, sexual sins are actually the worst. These latter two Catholic reactions will be discussed below: the first with logic and the second with Aquinas.

Pope Francis’s Words

Instead of relying on reports, let’s base ourselves on the transcript. Pope Francis was asked a series of questions about the resignation of the archbishop of Paris, Archbishop Aupetit. He began his response to one:

Pope Francis & Thomas Aquinas ( Nir Hason CC BY-SA 3.0 &  CC BY-SA 4.0)
Pope Francis & St. Thomas Aquinas (Nir Hason CC BY-SA 3.0 & CC BY-SA 4.0)

Before answering I will say: do the investigation, eh, do the investigation … because there is a danger of saying: he was condemned. Who condemned him? Public opinion, gossip. But what did he do? We don’t know, something … If you know why, say so, otherwise I cannot answer and you will not know why. Because it was his failure, a fault against the sixth commandment — but not total — of small caresses and massages that he gave to the secretary, so stands the accusation. This is sin, but it is not of the most serious sins, because the sins of the flesh are not the most serious. The gravest sins are those that are more angelic: pride, hatred. These are graver. So Aupetit is a sinner, as am I — I don’t know if you are aware … but probably — as was Peter, the bishop on whom Jesus Christ founded the Church.

I made the important lines bold to make it clear.

All Mortal Sins are the Same

Obviously, sexual sins are often mortal sins. I don’t think any serious Catholic can debate this. Some Catholics, however, want to absolutize the Mortal-Venial distinction too far. They say something to the effect of “all mortal sins are equally serious.”

This may seem plausible at first glance, as they can all keep you from Heaven, but a cursory glance deeper indicates otherwise. Is stabbing someone once with full knowledge and deliberate consent such that they need to go to the hospital to get 8 stitches a moral sin? Yes. Is doing the same, but intentionally stabbing exactly into the heart to kill them a mortal sin? Yes. I think it’s obvious that killing is worse than injuring. That is of a similar category of mortal sin to show it more obviously. Almost every serious moral theologian also distinguishes seriousness between categories of mortal sins.

Aquinas on Sexual Sins

In two places of the Summa, St. Thomas Aquinas says that sexual sins are not the most serious sins. They are similar but I will quote both. I will quote the “sed contra” and the whole body of each article but leave you to follow links if you want to see the objections and replies.

When comparing sins

I-II q.73 a.5

Whether carnal sins are of less guilt than spiritual sins? […]

On the contrary, Gregory says (Moral. xxxiii, 11) that carnal sins are of less guilt, but of more shame than spiritual sins.

I answer that, Spiritual sins are of greater guilt than carnal sins: yet this does not mean that each spiritual sin is of greater guilt than each carnal sin; but that, considering the sole difference between spiritual and carnal, spiritual sins are more grievous than carnal sins, other things being equal. Three reasons may be assigned for this.

[1.] The first is on the part of the subject: because spiritual sins belong to the spirit, to which it is proper to turn to God, and to turn away from Him; whereas carnal sins are consummated in the carnal pleasure of the appetite, to which it chiefly belongs to turn to goods of the body; so that carnal sin, as such, denotes more a “turning to” something, and for that reason, implies a closer cleaving; whereas spiritual sin denotes more a “turning from” something, whence the notion of guilt arises; and for this reason it involves greater guilt.

[2.] A second reason may be taken on the part of the person against whom sin is committed: because carnal sin, as such, is against the sinner’s own body, which he ought to love less, in the order of charity, than God and his neighbor, against whom he commits spiritual sins, and consequently spiritual sins, as such, are of greater guilt.

[3.] A third reason may be taken from the motive, since the stronger the impulse to sin, the less grievous the sin, as we shall state further on (Article 6). Now carnal sins have a stronger impulse, viz. our innate concupiscence of the flesh. Therefore spiritual sins, as such, are of greater guilt.

The sins of the flesh specifically

II-II q.154 a.3

Whether fornication is the most grievous of sins? […]

On the contrary, Gregory says (Moral. xxxiii, 12) that the sins of the flesh are less grievous than spiritual sins.

I answer that, The gravity of a sin may be measured in two ways, first with regard to the sin in itself, secondly with regard to some accident. The gravity of a sin is measured with regard to the sin itself, by reason of its species, which is determined according to the good to which that sin is opposed. Now fornication is contrary to the good of the child to be born. Wherefore it is a graver sin, as to its species, than those sins which are contrary to external goods, such as theft and the like; while it is less grievous than those which are directly against God, and sins that are injurious to the life of one already born, such as murder.

Now Aquinas is not infallible. However, when the Pope is simply paraphrasing Thomas Aquinas, I find it hard to fault him.

The broader answers and context here also point out how wrong others were to assume that sexual sins are unimportant. Aquinas in no way downplays them, but he puts them in a proper context of different sins.

The Constant Battle Against Sin

We need to constantly fight sin. Sexual sins seem most obvious, but Pope Francis and Aquinas remind us that other spiritual sins are more serious. This can be a challenge for us as often we struggle with these sins even after we have conquered sins of the flesh.

Updates: Other Theologians on Sexual Sins vs. Other Sins

Several people sent me other significant and orthodox moral theologians saying similar things.

Fr. John Ford, SJ & Fr. Gerald Kelly, SJ

Someone on Catholic Theology Geeks on Facebook noted that Fr. John Ford, SJ made a similar point about the gravity of different mortal sins. (Fr. Ford is one of the greatest Catholic moral theologians of the 20th century and together with then-Archbishop Karol Wojtyla wrote Paul VI to help provide a basis for Humanae Vitae, so incredibly orthodox.)

“In the second place, one must consider the degrees of gravity in mortal sins. It will obviously be more imprudent to expose oneself to the probable danger of committing a very great mortal sin than a lesser mortal sin. Mortal sins admit of indefinite degrees of gravity, too, from a solitary internal sin of thought, to an external sin, to a sin that affects one or several other persons, to sins that damage the goods or bodies or souls of others, to sins that damage the public good of the community or the nation or the Church of Christ itself. Since prudence is the criterion, it will take much greater necessity to justify entering an occasion of one of these greater sins. And a lesser degree of danger will be seriously rash when the sin is one of greater gravity. Accordingly, some theologians who would not admit that voluntarily entering probable danger is always mortally sinful, would agree that it is so in the case of particularly scandalous sins.”

Frs. John Ford SJ & Gerald Kelly SJ, Contemporary Moral Theology Volume I, pp. 152-153

Fr. John McHugh OP & Fr. Charles Callan OP

A person on Twitter DMed me this. Not as well known of theologians.

“Are sins against faith more serious than all other kinds of sin? (a) From their nature, sins against faith are worse than sins against the moral virtues, for the former offend directly against God Himself, but not so the latter. Hatred of God, however, is a greater sin than sins of unbelief, as will be shown when we treat of sins against charity. (b) From their circumstances, sins against faith may be less serious than sins against the moral virtues. Example: A venial sin against faith is less serious than a mortal sin against justice”

Fr. John McHugh OP & Fr. Charles Callan OP, Moral Theology: A Complete Course Based on St. Thomas Aquinas and the Best Modern Authorities, par. 820
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  1. When our Lady of Fatima showed hell to three children with innumerable sparks/souls falling into the lake of fire, she added that most go to hell because of sins of the flesh. Now pardon me, I prefer to take her word rather than that of Bergoglio, or Aquinas for that matter, in spite of my admiration for the latter.

    1. I think you need to look at quality vs. quantity. The fact more people go to hell for X does not imply X is worse. More people steal from the convenience store than the jewelry shop, but it’s worse to steal from he jewelry shop as the items are hundreds or thousands of dollars, not $1-2.

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