And the LORD said unto Moses,
When you go
to return into Egypt, see that you do all those wonders before Pharaoh, whom I have put in your hand: but I will harden his heart, that he shall not let the people go.
All Commentaries on Exodus 4:21 Go To Exodus 4
George Leo Haydock
AD 1849
I shall harden Not by being the efficient cause of his sin; but by withdrawing from him, for his just punishment, the dew of grace, that might have softened his heart; and so suffering him to grow harder and harder. (Challoner)
Non impertiendo misericordiam. (St. Augustine, ep. 194, ad Sixt.) Thus God permitted the false miracles of the magicians, and did not suffer the scourges to continue long, so that the tyrant soon relapsed and forgot his promises. (Origen, Philos. xx; Theodoret in Rom. ix. 17.) (Calmet)