And the LORD said unto Cain,
Where is Abel
your brother?
And he said, I know not: Am I my brother's keeper?
All Commentaries on Genesis 4:9 Go To Genesis 4
Salvian the Presbyter
AD 429
Cain was at once the most wicked and foolish of men in believing that for committing the greatest of crimes it would be sufficient if he avoided other human witnesses. In fact God was the primary witness to his fratricide. Because of this, I think he then shared the opinion held by many today: that God pays no attention to earthly affairs; neither does he see those done by wicked men. There is no doubt that Cain, when summoned by the word of God after his misdeed, answered that he knew nothing of his brother’s murder. He believed God was so ignorant of what had been done that he thought this most deadly crime could be covered by a lie. But it turned out otherwise than he thought. When God condemned him, he realized that God, whom he thought had not seen his crime of murder, had seen him.