The Sixth & Ninth Commandments
"Thou shalt not commit adultery"
"Thou shalt not covet thy neighbor's wife"
COMPENDIUM
This Sixth Commandment forbids every act, look or word against chastity and unfaithfulness in matrimony. The Ninth Commandment forbids expressly every desire contrary to the oath of mutual fidelity which the married pair have sworn to each other in their marriage contract; and it forbids even guilty thoughts or the desire of doing acts forbidden by the Sixth Commandment.
Impurity is a most grave and abominable sin in the eyes of God and men; for it degrades man to the state of the brute, and draws him into many other sins and vices, and provokes the most terrible penalties in this life and in that which is to come. It must not, however, be supposed that every thought occurring to the mind against purity is in itself a sin, but it should be regarded as a temptation and incentive to sin, and such thoughts, even if they do not result in acts or consequences, become sins if we guiltily afford grounds for them, or consent to them, or expose ourselves to the proximate danger of consenting to them.
Furthermore, the Sixth Commandment bids us be chaste and modest in look, demeanor and word; and the Ninth Commandment prescribes chastity and purity even within us, i.e., in mind and heart.
The only way to keep these two Commandments is to pray frequently from our hearts to God, to be devout to the Virgin Mary, the Mother of Purity, to bear in mind that God sees us, to think of death, the divine judgments, and the Passion of Jesus Christ, to keep watch over our senses, to practice Christian mortification, and to frequent the Sacraments with proper dispositions. To preserve chastity it is well to avoid idleness, bad company, reading bad newspapers and books, intemperance, looking at indecent pictures, licentious performances, risky conversations, and all other occasions of sin.
CATECHISM
423. What does the Sixth Commandment, Thou shalt not commit adultery, forbid?
The Sixth Commandment, Thou shalt not commit adultery, forbids every act, every look and every word contrary to chastity; it also forbids infidelity in marriage.
424. What does the Ninth Commandment, Thou shalt not covet thy neighbor's wife, forbid?
The Ninth Commandment, Thou shalt not covet thy neighbor's wife, expressly forbids every desire contrary to that fidelity which husband and wife vowed to observe when contracting marriage; and it also forbids every guilty thought or desire of anything that is prohibited by the Sixth Commandment.
425. Is impurity a great sin?
Impurity is a most grave and abominable sin in the sight of God and man; it lowers man to the condition of the brute; it drags him into many other sins and vices; and it provokes the most terrible chastisements both in this world and in the next.
426. Is every thought that comes into the mind against purity a sin?
The thoughts that come into the mind against purity are not of themselves sins, but rather temptations and incentives to sin.
427. When is a bad thought a sin?
Bad thoughts, even though resulting in no bad deed, are sins when we culpably entertain them, or consent to them, or expose ourselves to the proximate danger of consenting to them.
428. What do the Sixth and Ninth Commandments command?
The Sixth Commandment commands us to be chaste and modest in act, in look, in behavior, and in speech. The Ninth Commandment commands us in addition to this to be chaste and pure interiorly, that is, in mind and in heart.
429. What must we do to observe the Sixth and Ninth Commandments?
To be able to observe the Sixth and Ninth Commandments, we ought to pray often and from our hearts to God; be devout to the Blessed Virgin, the Mother of Purity; remember that God watches us; think on death, on the divine chastisements, and on the Passion of Jesus Christ; guard the senses; practice Christian mortification; and frequent the Sacraments with the proper dispositions.
430. What must we avoid in order to preserve ourselves chaste?
To preserve ourselves chaste we must shun idleness, bad companions, the reading of bad books and papers, intemperance, the sight of indecent statues or pictures, licentious theaters, dangerous conversations, and all other occasions of sin.