The Catholic teaching of this matter is given to us by God Himself
in Sacred Scripture:
XIII, 13: "And the men of Sodom were very
wicked, sinners before the face of the Lord, beyond measure";
these Sodomites were in fact homosexuals, as it is proven by Genesis
XVIII, 22,24-30: "Thou shalt not lie with
mankind as with womankind, because it is an abomination. (...)
Defile not yourselves with any of these things with which all
the nations have been defiled, which I will cast out before you.
And with which the land is defiled: the abominations of which
I will visit, that it may vomit out its inhabitants. Keep ye
my ordinances and my judgments, and do not any of these abominations:
neither any of your own nation, nor any stranger that sojourneth
among you. For all these detestable things the inhabitants of
the land have done, that were before you, and have defiled it.
Beware then, lest in like manner, it vomit you also out, if you
do the like things, as it vomited out the nation that was before
you. Every soul that shall commit any of these abominations,
shall perish from the midst of his people. Keep my commandments.
Do not the things which they have done, that have been before
you, and be not defiled therein. I am the Lord your God".
XX, 13: "If any one lie with a man as with
a woman, both have committed an abomination, let them be put to
death: their blood be upon them".
XXIII, 18: "Thou shalt not offer the
hire of a strumpet, nor the price of a dog, in the house of the
Lord thy God, whatsoever be that thou hast vowed: because both
these are an abomination to the Lord thy God".
I, 26-27, 31-32: "For this
cause God delivered them up to shameful afflictions. For their
women have changed the natural use into that use which is against
nature. And in like manner the men also, leaving the natural
use of the women, have turned in their lusts one towards another,
men with men working that which is filthy, and receiving in themselves
the recompense which was due to their error. (...) Foolish,
dissolute, without affection, without fidelity, without mercy.
Who, having known the justice of God, did not understand that
they, who do such things, are worthy of death: and not only they
that do them, but they also that consent to them that do them.
VI, 9-10: "Know you not that the unjust
shall not possess the kingdom of God? Do not err: Neither fornicators,
nor idolaters, nor adulterers. Nor the effeminate, nor liars
with mankind, (...) shall possess the kingdom of God". See
Genesis XIX, 12-29. Consequently, St. Augustine says (1) "that
of all these - namely the sins belonging to lust - that which
is against nature is the worst," is ”in itself a mortal sin,"
(2) a sin specifically distinct (3) from all other sins.
Why is homosexuality an "abomination", excluding from
the heavenly kingdom?
homosexuality is against nature: In the natural order planned
by God, the purpose of the carnal union is generation. Now, generation
is the natural fruit of the carnal union of man and woman. Therefore
the carnal union of two persons of the same sex goes against the
natural order planned by God.
homosexuality is against reason: Reason presupposes things
as determined by nature, before disposing of other things according
as it is fitting. Now, in matters of action, it is most grave
and shameful to act against things as determined by nature. Therefore,
since the homosexual transgresses that which has been determined
by nature with regards to the use of sexual actions, it follows
that he acts against reason.
Thoughts of some Doctors of the Church about homosexuality:
St. Augustine: "Those foul offences that
are against nature should be everywhere and at all times detested
and punished, such as were those of the people of Sodom, which
should all nations commit, they should all stand guilty of the
same crime, by the law of God, which hath not so made men that
they should so abuse one another. For even that very intercourse
which should be between God and us is violated, when that same
nature, of which He is the Author, is polluted by the perversity
of lust". (Confessions; III.8)
St. John Chrysostomus: "The
worst of it is that such an abomination is committed boldly and
that the monstrosity becomes the law. Nobody nowadays fears,
nobody blushes. They boast and they laugh at these actions.
The people who abstain appear stupid and they who condemn are
regarded as fools. If they appear to be the weaker ones they
are crushed with blows. If they are stronger, people laugh, people
mock them and make many jokes about them. They have no redress
in tribunals or in law." (...) "I have heard also many
men who are surprised that up to the present a new shower of fire
has not fallen on us and that the chastisement of Sodom has not
fallen again on our town which is even more deserving of punishment
since it did not learn from the evils of the Sodomites. Although
after two thousand years this place accursed and overwhelmed which
was Sodom cries to the whole world by its appearance more eloquently
than any one voice could, not to dare to commit such heinous offences,
our fellow citizens have committed these offences not with less
effrontery but quite on the contrary they show themselves more
daring and unashamed as if they were determined to do battle with
God and that they wish to prove that they wish to add to their
crimes, in proportion as the threats become more terrible. How
is it that according as the crimes of Sodom renew themselves the
chastisement of Sodom is not also renewed? Ah, the reason is
that a more terrible fire waits them and that a chastisement is
reserved for them which will have no end." (Against the
opponents of Monastic Life, III.8)
(1) De adult.
conjug.; cap. Adulterii; cause 32; q 7; quoted by St. Thomas Aquinas:
Summa Theologica; II II q 154, a 12.
Thomas Aquinas: De Malo; q xv, a 2, ad 6.
Alexander VII: Decree from the Holy Office, Sept. 24, 1665 prop.
No. 24. (Dzs. 2044).