Curse and mark of Cain

The curse of Cain and the mark of Cain are phrases that originated in Genesis 4, where God declared that Cain (the firstborn son of Adam and Eve) would be cursed for murdering his brother Abel. A mark was put upon him in order to warn others that killing Cain would provoke the vengeance of God, that if someone did something to harm Cain, the damage would come back sevenfold. Some interpretations view this as a physical mark, whereas other interpretations see the "mark" as a sign, and not as a physical marking on Cain himself. The King James Version of the Bible reads "set a mark upon Cain".