Reply #5: Not his fault. It's true. The etymology website says so

[Ian David]

elder son of Adam and Eve, from Heb. Qayin, lit. "created one," also "smith," from Sem. stem q-y-n "to form, to fashion." To raise Cain is first recorded 1840. Surnames McCain, McCann, etc., are a contraction of Ir. Mac Cathan "son of Cathan," from Celt. cathan, lit. "warrior," from cath "battle."
http://www.etymonline.com/index.php?term=Cain


Actually, it says he's wrong about the INTENDED meaning of the word McCain.

But if god chose to give him a name which CAN mean "Son of Cain," then it's just as important as if god had given him a name in which the numbers add up to 666, or if god gave him the middle name "Hussein."