As used in the Bible, adultery generally refers to voluntary sexual intercourse by a married person with one of the opposite sex other than one’s mate, or, during the time that the Mosaic Law was in effect, such intercourse by any man with a married or a betrothed woman. The Hebrew root meaning “commit adultery” is na·ʼaphʹ, while its Greek counterpart is moi·kheuʹo.
Certain primitive societies allow free relations within the same tribe, but promiscuity outside tribal bounds is considered adultery. On the history of adultery, Funk & Wagnalls Standard Dictionary of Folklore, Mythology and Legend (1949, Vol. 1, p. 15) says: “It occurs in all parts of the world and though it is considered reprehensible by many cultures it has enjoyed a considerable popularity in all cultures and at all times.” Monuments attest to its prevalence in ancient Egypt; Potiphar’s wife, who proposed that Joseph have relations with her, was such an Egyptian. (Ge 39:7, 10) Historically as well as at present, adultery is generally forbidden, but penalties are seldom imposed.
Jehovah’s law separated Israel and raised the moral status of marriage and family life to a much higher level than that of the surrounding nations. The seventh commandment of the Decalogue stated in direct, unmistakable language: “You must not commit adultery.” (Ex 20:14; De 5:18; Lu 18:20) Adulterous invasion of another man’s domain was prohibited, as were other forms of sexual misconduct.
Under the Law of Moses the penalty for adultery was severe
Christians, though not under Mosaic Law, must also refrain from adultery. “For the law code, ‘You must not commit adultery,’ . . . is summed up in this word, namely, ‘You must love your neighbor as yourself.’” There can be no hypocrisy in this matter. (Ro 13:9; 2:22) In teaching Bible principles, Jesus raised the moral standard still higher for Christians. He broadened out the matter of adultery, saying it was not limited to sexual contact a man might have with a woman not his mate: “Everyone that keeps on looking at a woman so as to have a passion for her has already committed adultery with her in his heart.” Such men are among those who “have eyes full of adultery.”
Jesus also pointed out that if a divorce was obtained by either husband or wife, except on the ground of fornication (Gr., por·neiʹa), the remarriage of either one would constitute adultery. Even a single man who took such a divorced woman as his wife would be guilty of adultery.
Adultery is “actually sin against God.” (Ge 39:9) Jehovah will judge those guilty of adultery, and none who persist in such a course “will inherit God’s kingdom.” (Mal 3:5; 1Co 6:9, 10; Heb 13:4) How true the proverb: “Anyone committing adultery with a woman is in want of heart; he that does it is bringing his own soul to ruin.”
How could one become guilty of spiritual adultery?
In a spiritual sense, adultery denotes unfaithfulness to Jehovah on the part of those who are joined to him in a covenant. Natural Israel in the Law covenant was, therefore, guilty of spiritual adultery because of false religious practices, some of which included sex-worship rites and disregard for the seventh commandment. (Jer 3:8, 9; 5:7, 8; 9:2; 13:27; 23:10; Ho 7:4) For similar reasons Jesus denounced as adulterous the generation of Jews in his day. (Mt 12:39; Mr 8:38) Likewise today, if Christians who are dedicated to Jehovah and who are in the new covenant defile themselves with the present system of things, they commit spiritual adultery.