I always thought that the critical response from Cain to God's query about Abel's whereabouts after the first human-on-human crime tells us everything we need to know about our choice in this world: השומר אחי אנכי. Read as a question, it's Cain being coy. Read as a statement, it's Cain admitting to his failing. The reader chooses. (I bring this down from the RagBam, obviously.)
I always thought that the critical response from Cain to God's query about Abel's whereabouts after the first human-on-human crime tells us everything we need to know about our choice in this world: השומר אחי אנכי. Read as a question, it's Cain being coy. Read as a statement, it's Cain admitting to his failing. The reader chooses. (I bring this down from the RagBam, obviously.)
Elu v'Elu as they say...