Adultery, by definition, is the violation of the marriage contract by either or both partners through sexual activity with a third person, but this commandment against adultery should also be understood to include fornication (sexual relations before marriage), incest and male and female homosexual practices, all of which are outlawed in the Bible.
Adultery is considered a serious sin by Almighty God, and its prohibition constitutes one of the Ten Commandments: "You shall not commit adultery" (Exodus 20:14; Deuteronomy 5:18). In ancient Israel adulterers suffered capital punishment (Leviticus 20:10), and the sin is described as an abomination in God's eyes (verse 13).
Some may feel that any sexual activity short of intercourse is not a sin, but Scripture shows that anything involving "uncovering nakedness"—for the purpose of sexual misbehaviour—is a sin (Leviticus 18:6-19). Jesus Christ instructed that even desiring to interact sexually with someone other than your marriage partner is a sin (Matthew 5:28).
Illicit love affairs are often depicted in a favorable light in films and other entertainment media, with the purveyors of popular culture neglecting to focus on the dark side of adultery. Jonathan Rauch, correspondent for ‘The National Journal’ in Washington, D.C., observed that "adultery represents a serious problem for society as well as individuals.... Marriage civilizes and settles men (especially younger men), promotes secure homes for children, helps achieve economic stability for both partners, ensures that everyone has somebody to look after him or her in times of ill health. To serve these functions marriages must be durable."
Not only has an adulterer broken the marriage vow, but he or she has also put another person before God—thereby breaking the First and Second Commandments. Adultery shows no respect for parents and in-laws who also suffer when adultery is committed — breaking the Fifth Commandment (Exodus 20:12). The Eighth and Ninth Commandments are also transgressed in that the affection, love and trust of someone else's spouse is stolen (verse 15), and lying and deceit are involved (verse 16).
As Jonathan Rauch put it: "An adulterer is a missile with many warheads, capable of wrecking a series of homes." It often leads to divorce, which in turn divides families. Not only are the husband and wife affected, but the children, any grandchildren, parents on both sides and even society at large. A British survey on the reasons for divorce showed that adultery was the biggest reason by far, contributing to 31 percent of divorces (The Daily Mail, Jan. 26), and that in Britain "it's an uncomfortable fact that 50 percent of divorced and separated fathers lose contact with their children after just two years" (Independent on Sunday, Feb. 15). No wonder Malachi 2:16 says that God hates divorce.
God cared enough for King David that, after his act of adultery, which led to deceit and murder, He sent the prophet Nathan to help him repent. "Why have you despised the commandment of the Lord... You have killed Uriah the Hittite...you have taken his wife to be your wife … Now therefore, the sword shall never depart from your house, because you have despised Me..." (2 Samuel 12:9-10). Others who hold high office have fallen victim to this sin and this sadly includes, not only politicians and royalty, but religious leaders, who should know better.
This is not to say those who have committed adultery cannot repent and be forgiven. When the woman caught in the act of adultery (John 8) was brought before Jesus, He defended her by turning to her accusers and saying, "He who is without sin among you, let him throw a stone at her first" (verse 7). Jesus then admonished the woman to, "Go and sin no more" (verse 11). He did not defend her sin, and He unequivocally told her not to sin again. Sincere repentance must take place, as was the case with King David (2 Samuel 12:13, Psalm 51).
Our current Western society takes infidelity far too lightly. Not only should our leaders, both political and religious, strive to set the right example but, as Christians, we should endeavour to be the kind of examples Jesus Christ described and to “... Let your light so shine before men, that they may see your good works and glorify your Father in heaven" (Matthew 5:14-16).