"Am I My Brother's Keeper?"
Context: After their expulsion from the Garden of Eden, Adam and Eve have two sons: Cain, the elder, and Abel, the younger. Cain is described as "a tiller of the ground," and Abel as "a keeper of sheep." In due time Cain brings an offering to the Lord "of the fruit of the ground," while Abel brings one of his sheep. The Lord is pleased with the offering of Abel, but for that of Cain "he had not respect." Cain then, very impiously, becomes angry with the Lord, for which offence he is sternly rebuked by God. In anger and despair Cain then kills Abel, but the murder does not escape the Lord's watchfulness: Cain is accursed and made a vagabond, but a mark is set upon him (the "mark of Cain") lest someone slay him. Cain then flees into the Land of Nod, "on the east of Eden." The Lord's question to Cain and Cain's reply, after the murder, are:
And the Lord said unto Cain, Where is Abel thy brother?And he said, I know not: Am I my brother's keeper?