The Seventh Commandment of the Law of God
“You shall not commit adultery.”
By this commandment, the Lord God commands husband and wife to keep mutual fidelity, and the unmarried to be chaste — pure in deeds, words, thoughts, and desires. To avoid sinning against the seventh commandment, one must avoid everything that arouses impure feelings, such as: foul language, “spicy” anecdotes, shameless songs and dances, watching seductive films and photographs, reading immoral magazines. Explaining the seventh commandment in the Sermon on the Mount, the Lord says: “Whoever looks at a woman to lust for her has already committed adultery with her in his heart.” (Mt. 5:28).
To avoid impure desires, sinful thoughts must be cut off at the very moment of their arising, without allowing them the opportunity to take possession of our feelings and will. The Lord, as the Knower of hearts, knows how difficult it is for a person to struggle with carnal temptations, therefore He teaches us to be resolute and merciless toward ourselves when they come: “If your right eye causes you to sin, pluck it out and cast it from you; for it is more profitable for you that one of your members perish, than for your whole body to be cast into hell.” (Mt. 5:29). Here is figurative speech, which can be rephrased as follows: If someone is as dear to you as your own eye or hand, but tempts you, then without delay cease all communication with the tempter. It is better for you to lose his friendship and services than eternal life.
Regarding the duty of spouses to keep mutual fidelity, the Lord Jesus Christ said: “What God has joined together, let not man separate.” (Mt. 19:6).
A grave sin against the seventh commandment is homosexuality. Debauchees in every way try to justify this sin. This shameful sin the Apostle Paul severely condemns in the first chapter of his Epistle to the Romans (vv. 21–32). The ancient cities of Sodom and Gomorrah were destroyed by God precisely for this sin (Genesis, chapter 19; see the Catholic Epistle of the Apostle Jude 1:7). Regarding carnal licentiousness, Scripture warns: “Fornicators sin against their own body.” “Fornicators and adulterers God will judge.” (1 Cor. 6:18; Heb. 13:4). Unrestrained life weakens health, weakens a person’s mental abilities, especially — his imagination and memory. One must preserve one’s moral purity, because our bodies are “members of Christ and temples of the Holy Spirit.”