Cain
A son of Adam and Eve who slew his younger brother Abel over jealousy and greed (Gen. 4:1–16). Some of his descendants were skilled in the use of the harp and organ and in working with brass and iron (Gen. 4:17–25). Due to the incompleteness of the biblical record, many have regarded Cain as the eldest son of Adam. However, latter-day revelation tells us that Adam and Eve had many sons and daughters before Cain was born (Moses 5:1–3, 16–18). He married one of his brothers’ daughters (Moses 5:28).
Cain’s offering was rejected by the Lord, probably for several reasons, including the fact that it was not done in faith nor in the prescribed and revealed manner (compare Moses 5:5–8 with Gen. 4:3–5). He entered into an unholy covenant with Satan by which he became known as Master Mahan, or “master of this great secret,” and by which he could “murder and get gain” (Moses 5:29–31). A mark was set upon him by which he could be distinguished from the other children of Adam (Gen. 4:15; Moses 5:38–41). Cain and his descendants lived separately from the other descendants of Adam (Moses 7:22).
Cain is mentioned frequently in the scriptures, including Heb. 11:4; 1 Jn. 3:12; Jude 1:11; Hel. 6:27; Ether 8:15; Moses 5–7; see also D&C 84:16.