This chapter contains one of the most well known--and one of my favorite--Bible stories, including the famous question, "Am I my brother's keeper?" Like all Bible narratives, it is very succinct, offering only the facts and not even all of those--such as exactly how Cain killed Abel, or what their conversation in the field sounded like. It is possible that Abel was bragging and rubbing in his favor with God--not that that would excuse murder, but it would certainly cast the story in a different light. This is one of the things I like about reading the Bible; the stories leave so much room for interpretation, it is possible to have many different and even opposing views about the same story.
The plight of Cain after the murder has always been of special interest to me--I even tried writing a poem about it once (I thankfully don't have a copy of my many unfinished attempts around). It always seemed to me like wandering around forever marked off from others is worse than death. Cain becomes a perpetual "other;" people will want nothing to do with him because of the sin and because he has been marked by God. The mark itself does two things--it warns others not to kill him, and it shows that he has been touched by God, making him something strange and therefore scary.
The really interesting question, supposing that this really is a worse punishment than death, becomes whose fault this punishment is. One could see God as the punisher--he is, after all, the one that decides Cain needs punishing in the first place, and his first idea is pure banishment and alienation. This is accomplished even more fully with the mark, because it won't be over anytime soon. It is Cain, however, who insists he needs some sort of protection, resulting in the mark. Perhaps this further reflects the smallness of his spirit; fear of death stops him from seeking the peace he might otherwise have had.
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