The unlawful sexual association of men and women. Although adultery generally refers to sexual intercourse between a married person and someone other than his or her spouse, in the scriptures it may also refer to the unmarried.

Sometimes adultery is used as a symbol for the apostasy of a nation or a whole people from the ways of the Lord (Num. 25: 1-3; Ezek. 16: 15-59; Jer. 3: 6-10; Hosea 4).

Joseph would not do this great wickedness, and sin against God, Gen. 39: 7-12. Thou shalt not commit adultery, Ex. 20: 14. Whosoever looketh on a woman to lust after her hath committed adultery in his heart, Matt. 5: 28. Neither fornicators nor adulterers shall inherit the kingdom of God, 1 Cor. 6: 9-10. God will judge whoremongers and adulterers, Heb. 13: 4. Adultery is most abominable above all sins save it be the shedding of innocent blood or denying the Holy Ghost, Alma 39: 3-5. He that committeth adultery, and repenteth not, shall be cast out, D&C 42: 23-26. If any shall commit adultery in their hearts, they shall not have the Spirit, D&C 63: 14-16.