Now you are cursed and banished from the ground, which has opened its mouth to receive your brother’s blood from your hand.
11. And now art thou cursed from the earth . Cain, having been convicted of the crime, judgment is now pronounced against him. And first, God constitutes the earth the minister of his vengeance, as having been polluted by the impious and horrible parricide: as if he had said, ‘Thou didst just now deny to me the murder which thou hast committed, but the senseless...
We have here a full account of the trial and condemnation of the first murderer. Civil courts of judicature not being yet erected for this purpose, as they were afterwards (Gen 9:6), God himself sits Judge; for he is the God to whom vengeance belongs, and who will be sure to make inquisition for blood, especially the blood of saints. Observe, I.
Commenting on Genesis 4:9-12
When thou tillest the ground,.... Which was the business he was brought up in and followed, Gen 4:2. it shall not henceforth yield unto thee her strength; the earth had been cursed for Adam's sin, and was not so fruitful as in its original state; and now it was cursed again for Cain's sin; not the whole earth, but that part which belonged to Cain...