The saying of "Love your neighbor as yourself" is one of the most famous and also one of the most fundamental statements in the Torah. (Lev. 19:18) The saying of "You are your brother's keeper" is actually paraphrasing a statement made by Cain. When Cain was confronted by God and asked where was his brother Abel (who he had just murdered) he answered cynically "Am I my brother's keeper?" (Gen. 4:9) Cain was trying to deflect both the responsibility for what he had just done and also to try and distance himself from any general responsibility that one has toward another person, and was punished by God.
