The message of the seventh commandment is one that modern man seems to have outgrown. The command, “Thou shalt not commit adultery” (Exodus 20:14), seems outdated in our sophisticated times. The idea of monogamous marriage seems stifling to many in an era of sexual freedom. Few realize, however, that this command opens the door to true sexual freedom and expression, and is liberating, rather than burdensome. 

The focus of scripture is not on preventing adultery as much as it is in developing fulfilling marriage. “Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh” (Genesis 2:24). Marriage involves a commitment, both emotionally and physically, and when that commitment is made, the two so joined must remain committed. The seventh commandment also limits sexual intercourse to marriage, and thus forbids it to those who are unmarried. It is strictly a privilege of husband and wife. Sex is not wrong. It is God’s gift. He limits it, however, to the marriage relationship. When God’s gift is misused, calamity results. 

In the Old Testament era, some practiced polygamy. Although sometimes done for humanitarian reasons, such as the care of a widow, or of a brother’s wife, many such as Abraham, David, and Solomon reaped bitter fruit from the practice. Too many today practice “serial polygamy” by taking one mate after another, without considering the consequences. “Now the body is not for fornication, but for the Lord; and the Lord for the body. … Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body. What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God’s” (1 Corinthians 6:13b, 18-20). 

Jesus reprimanded the Pharisees, reminding them that adultery is a sin committed with the mind as well as the body. “Ye have heard that it was said by them of old time, Thou shalt not commit adultery: But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart” (Matthew 5:27-28). Jesus considered fornication, or adultery, so serious that it is the one cause for divorce (Matthew 5:31-32; Matthew 19:3-19). 

Jesus came to seek and save the lost, and His ministry included offering forgiveness to those involved in sexual sin, such as the adulterous woman brought before Him. He showed her grace. “Neither do I condemn thee: go, and sin no more” (John 8:11). He balanced forgiveness with repentance and a desire to end sin. 

Fidelity in the marriage relationship is important, because it reflects the relationship that God wants to maintain with His people. The prophets equated the fall into idolatry with spiritual adultery. When man lusts after some of the gods of today, such as popularity, power, and sex, he commits spiritual adultery. All are subject to the lure of sin, so we must remain vigilant against all sin, especially the sin of adultery.