The Sixth Commandment
You shall not commit adultery.
As with all the commandments, the sixth commandment encompasses
much more than a single act. Regarding the marital act, the Catechism
says, “The union of man and woman in marriage is a way of imitating
leaves his father and mother and cleaves to his wife, and they become
The sixth commandment is really about chastity. The Catechism number
18
2339 says this: “Chastity includes an apprenticeship in self-mastery
which is a training in human freedom. The alternative is clear: either man
them and becomes unhappy.” It also tells us that “All the baptized are
called to chastity.” (CCC 2348)
The Catechism speaks of numerous offenses against chastity, including
lust, masturbation, homosexual acts, fornication, pornography, prostitution,
rape and incest. In fact, any sexual relations outside the sacramental
bond of marriage are forbidden. All of these stem from the words of Jesus
in Matthew 5:27-28 – “You have heard that it was said, ‘You shall not
commit adultery.’ But I say to you that everyone who looks at a woman
lustfully has already committed adultery with her in his heart.”
Finally, in its section on the sixth commandment, the Catechism includes
a section on The Love of Husband and Wife and speaks beautifully of
of life and love established by the Creator and governed by his laws; it
is rooted in the conjugal covenant, that is, in their irrevocable personal
For further study:
CCC 2331-2400
Matthew 5:27-28