Cain was the son of Adam and Eve and the cause of his
brother Abel's death. As
a farmer, he brought produce as an offering to God.
God favored Abel's sacrifice of lambs and Abel's jealousy incited him
to kill his brother. God asked Cain where his brother was and Cain responded
by saying "Am I my brother's keeper?" (Genesis
4:9) As a punishment God curses him to forever wander, but marked
him with a sign so that no on should kill him. Cain has one son, Enoch,
and is known as the father of the Kenites. The expression "mark
of Cain" is taken to mean the obvious sign of a murderer's guilt.
Sources: Bridger, David. Ed. The
New Jewish Encyclopedia, NY: Behrman House, 1976; Navigating
the Bible II