Talk:Mark of Cain
Cain kills Abel - and fears 'everyone on Earth' will slay him.
'Everybody' at this point consists of (1) Adam and Eve, (2) God and the angels and (3) the snake.
Even if there are other people - unless Cain names himself, they will not know who he was - and why would God not punish them for performing the same crime as Cain?
And taking the text at face value, the Mark of Cain #is only affixed to him# and not his descendants.
If the Mark was inherited, it would probably become widespread on passing through the Noah bottleneck (even if it had passed through one of the inlaws breeding would have spread it far and wide).