Whether Simple Fornication Is a Mortal Sin?
Objection 1: It would seem that simple fornication is not a mortal
sin. For things that come under the same head would seem to be on a
par with one another. Now fornication comes under the same head as
things that are not mortal sins: for it is written (Acts 15:29):
"That you abstain from things sacrificed to idols, and from blood,
and from things strangled, and from fornication." But there is not
mortal sin in these observances, according to 1 Tim. 4:4, "Nothing is
rejected that is received with thanksgiving." Therefore fornication
is not a mortal sin.
Obj. 2: Further, no mortal sin is the matter of a Divine precept. But
the Lord commanded (Osee 1:2): "Go take thee a wife of fornications,
and have of her children of fornications." Therefore fornication is
not a mortal sin.
Obj. 3: Further, no mortal sin is mentioned in Holy Writ without
disapprobation. Yet simple fornication is mentioned without
disapprobation by Holy Writ in connection with the patriarchs. Thus
we read (Gen. 16:4) that Abraham went in to his handmaid Agar; and
further on (Gen. 30:5, 9) that Jacob went in to Bala and Zelpha the
handmaids of his wives; and again (Gen. 38:18) that Juda was with
Thamar whom he thought to be a harlot. Therefore simple fornication
is not a mortal sin.
Obj. 4: Further, every mortal sin is contrary to charity. But simple
fornication is not contrary to charity, neither as regards the love
of God, since it is not a sin directly against God, nor as regards
the love of our neighbor, since thereby no one is injured. Therefore
simple fornication is not a mortal sin.
Obj. 5: Further, every mortal sin leads to eternal perdition. But
simple fornication has not this result: because a gloss of Ambrose
[*The quotation is from the Gloss of Peter Lombard, who refers it to
St. Ambrose: whereas it is from Hilary the deacon] on 1 Tim. 4:8,
"Godliness is profitable to all things," says: "The whole of
Christian teaching is summed up in mercy and godliness: if a man
conforms to this, even though he gives way to the inconstancy of the
flesh, doubtless he will be punished, but he will not perish."
Therefore simple fornication is not a mortal sin.
Obj. 6: Further, Augustine says (De Bono Conjug. xvi) that "what food
is to the well-being of the body, such is sexual intercourse to the
welfare of the human race." But inordinate use of food is not always
a mortal sin. Therefore neither is all inordinate sexual intercourse;
and this would seem to apply especially to simple fornication, which
is the least grievous of the aforesaid species.
_On the contrary,_ It is written (Tob. 4:13): "Take heed to keep
thyself . . . from all fornication, and beside thy wife never endure
to know a crime." Now crime denotes a mortal sin. Therefore
fornication and all intercourse with other than one's wife is a
mortal sin.
Further, nothing but mortal sin debars a man from God's kingdom. But
fornication debars him, as shown by the words of the Apostle (Gal.
5:21), who after mentioning fornication and certain other vices,
adds: "They who do such things shall not obtain the kingdom of God."
Therefore simple fornication is a mortal sin.
Further, it is written in the Decretals (XXII, qu. i, can.
Praedicandum): "They should know that the same penance is to be
enjoined for perjury as for adultery, fornication, and wilful murder
and other criminal offenses." Therefore simple fornication is a
criminal or mortal sin.
_I answer that,_ Without any doubt we must hold simple fornication to
be a mortal sin, notwithstanding that a gloss [*St. Augustine, QQ. in
Deut., qu. 37] on Deut. 23:17, says: "This is a prohibition against
going with whores, whose vileness is venial." For instead of "venial"
it should be "venal," since such is the wanton's trade. In order to
make this evident, we must take note that every sin committed
directly against human life is a mortal sin. Now simple fornication
implies an inordinateness that tends to injure the life of the
offspring to be born of this union. For we find in all animals where
the upbringing of the offspring needs care of both male and female,
that these come together not indeterminately, but the male with a
certain female, whether one or several; such is the case with all
birds: while, on the other hand, among those animals, where the
female alone suffices for the offspring's upbringing, the union is
indeterminate, as in the case of dogs and like animals. Now it is
evident that the upbringing of a human child requires not only the
mother's care for his nourishment, but much more the care of his
father as guide and guardian, and under whom he progresses in goods
both internal and external. Hence human nature rebels against an
indeterminate union of the sexes and demands that a man should be
united to a determinate woman and should abide with her a long time
or even for a whole lifetime. Hence it is that in the human race the
male has a natural solicitude for the certainty of offspring, because
on him devolves the upbringing of the child: and this certainly would
cease if the union of sexes were indeterminate.
This union with a certain definite woman is called matrimony; which
for the above reason is said to belong to the natural law. Since,
however, the union of the sexes is directed to the common good of the
whole human race, and common goods depend on the law for their
determination, as stated above (I-II, Q. 90, A. 2), it follows that
this union of man and woman, which is called matrimony, is determined
by some law. What this determination is for us will be stated in the
Third Part of this work (Suppl., Q. 50, seqq.), where we shall treat
of the sacrament of matrimony. Wherefore, since fornication is an
indeterminate union of the sexes, as something incompatible with
matrimony, it is opposed to the good of the child's upbringing, and
consequently it is a mortal sin.
Nor does it matter if a man having knowledge of a woman by
fornication, make sufficient provision for the upbringing of the
child: because a matter that comes under the determination of the law
is judged according to what happens in general, and not according to
what may happen in a particular case.
Reply Obj. 1: Fornication is reckoned in conjunction with these
things, not as being on a par with them in sinfulness, but because
the matters mentioned there were equally liable to cause dispute
between Jews and Gentiles, and thus prevent them from agreeing
unanimously. For among the Gentiles, fornication was not deemed
unlawful, on account of the corruption of natural reason: whereas
the Jews, taught by the Divine law, considered it to be unlawful.
The other things mentioned were loathsome to the Jews through custom
introduced by the law into their daily life. Hence the Apostles
forbade these things to the Gentiles, not as though they were
unlawful in themselves, but because they were loathsome to the Jews,
as stated above (I-II, Q. 103, A. 4, ad 3).
Reply Obj. 2: Fornication is said to be a sin, because it is contrary
to right reason. Now man's reason is right, in so far as it is ruled
by the Divine Will, the first and supreme rule. Wherefore that which
a man does by God's will and in obedience to His command, is not
contrary to right reason, though it may seem contrary to the general
order of reason: even so, that which is done miraculously by the
Divine power is not contrary to nature, though it be contrary to the
usual course of nature. Therefore just as Abraham did not sin in
being willing to slay his innocent son, because he obeyed God,
although considered in itself it was contrary to right human reason
in general, so, too, Osee sinned not in committing fornication by
God's command. Nor should such a copulation be strictly called
fornication, though it be so called in reference to the general
course of things. Hence Augustine says (Confess. iii, 8): "When God
commands a thing to be done against the customs or agreement of any
people, though it were never done by them heretofore, it is to be
done"; and afterwards he adds: "For as among the powers of human
society, the greater authority is obeyed in preference to the lesser,
so must God in preference to all."
Reply Obj. 3: Abraham and Jacob went in to their handmaidens with no
purpose of fornication, as we shall show further on when we treat of
matrimony (Suppl., Q. 65, A. 5, ad 2). As to Juda there is no need to
excuse him, for he also caused Joseph to be sold.
Reply Obj. 4: Simple fornication is contrary to the love of our
neighbor, because it is opposed to the good of the child to be born,
as we have shown, since it is an act of generation accomplished in a
manner disadvantageous to the future child.
Reply Obj. 5: A person, who, while given to works of piety, yields to
the inconstancy of the flesh, is freed from eternal loss, in so far
as these works dispose him to receive the grace to repent, and
because by such works he makes satisfaction for his past inconstancy;
but not so as to be freed by pious works, if he persist in carnal
inconstancy impenitent until death.
Reply Obj. 6: One copulation may result in the begetting of a man,
wherefore inordinate copulation, which hinders the good of the future
child, is a mortal sin as to the very genus of the act, and not only
as to the inordinateness of concupiscence. On the other hand, one
meal does not hinder the good of a man's whole life, wherefore the
act of gluttony is not a mortal sin by reason of its genus. It would,
however, be a mortal sin, if a man were knowingly to partake of a
food which would alter the whole condition of his life, as was the
case with Adam.
Nor is it true that fornication is the least of the sins comprised
under lust, for the marriage act that is done out of sensuous
pleasure is a lesser sin.
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