And the Lord said unto Cain. "Probably soon after the event, at the next time of sacrifice, and at the usual place of offering" (Bonar). Where is Abel thy brother? "A question fitted to go straight to the murderer's conscience, and no less fitted to rouse his wrathful jealousy, as showing how truly Abel was the beloved one" (ibid).
Whether spoken by Adam (Luther), or whispered within his breast by the still small voice of conscience, or, as is most probable, uttered from between the cherubim, Cain felt that he was being examined by a Divine voice (Calvin).
And (in reply) he said (adding falsehood, effrontery, and even profanity to murder), I know not: am I my brother's keeper? The inquiry neither of ignorance nor of innocence, but the desperate resort of one who felt himself closely tracked by avenging justice and about to be convicted of his crime.
"He showeth himself a lyer in saying, 'I know not; wicked and profane in thinking he could hide his sin from God; unjust in denying himself to be his brother's keeper; obstinate and desperate in not confessing his sin" (Willet; cf.