Exodus 4:21

But I will harden his heart - The case of Pharaoh has given rise to many fierce controversies, and to several strange and conflicting opinions. Would men but look at the whole account without the medium of their respective creeds, they would find little difficulty to apprehend the truth. If we take up the subject in a theological point of view, all sober Christians will allow the truth of this proposition of St. Augustine, when the subject in question is a person who has hardened his own heart by frequently resisting the grace and spirit of God: Non obdurate Deus impertiendo malitiam, sed non impertiendo misericordiam; Epist. 194, ad Sixtum, "God does not harden men by infusing malice into them, but by not imparting mercy to them." And this other will be as readily credited: Non operatur Deus in homine ipsam duritiam cordis; sed indurare eum dicitur quem mollire noluerit, sic etiam excaecare quem illuminare noluerit, et repellere eum quem noluerit vocare. "God does not work this hardness of heart in man; but he may be said to harden him whom he refuses to soften, to blind him whom he refuses to enlighten, and to repel him whom he refuses to call." It is but just and right that he should withhold those graces which he had repeatedly offered, and which the sinner had despised and rejected. Thus much for the general principle. The verb חזק chazak, which we translate harden, literally signifies to strengthen, confirm, make bold or courageous; and is often used in the sacred writings to excite to duty, perseverance, etc., and is placed by the Jews at the end of most books in the Bible as an exhortation to the reader to take courage, and proceed with his reading and with the obedience it requires. It constitutes an essential part of the exhortation of God to Joshua, Joshua 1:7 : Only be thou Strong, רק חזק rak chazak. And of Joshua's dying exhortation to the people, Joshua 23:6 : Be ye therefore Very Courageous, וחזקתם vachazaktem, to keep and to do all that is written in the book of the law. Now it would he very strange in these places to translate the word harden: Only be thou hard, Be ye therefore very hard; and yet if we use the word hardy, it would suit the sense and context perfectly well: Only be thou Hardy; Be ye therefore very Hardy. Now suppose we apply the word in this way to Pharaoh, the sense would be good, and the justice of God equally conspicuous. I will make his heart hardy, bold, daring, presumptuous; for the same principle acting against God's order is presumption, which when acting according to it is undaunted courage. It is true that the verb קשה kashah is used, Exodus 7:3, which signifies to render stiff, tough, or stubborn, but it amounts to nearly the same meaning with the above.

All those who have read the Scriptures with care and attention, know well that God is frequently represented in them as doing what he only permits to be done. So because a man has grieved his Spirit and resisted his grace he withdraws that Spirit and grace from him, and thus he becomes bold and presumptuous in sin. Pharaoh made his own heart stubborn against God, Exodus 9:34; and God gave him up to judicial blindness, so that he rushed on stubbornly to his own destruction. From the whole of Pharaoh's conduct we learn that he was bold, haughty, and cruel; and God chose to permit these dispositions to have their full sway in his heart without check or restraint from Divine influence: the consequence was what God intended, he did not immediately comply with the requisition to let the people go; and this was done that God might have the fuller opportunity of manifesting his power by multiplying signs and miracles, and thus impress the hearts both of the Egyptians and Israelites with a due sense of his omnipotence and justice. The whole procedure was graciously calculated to do endless good to both nations. The Israelites must be satisfied that they had the true God for their protector; and thus their faith was strengthened. The Egyptians must see that their gods could do nothing against the God of Israel; and thus their dependence on them was necessarily shaken. These great ends could not have been answered had Pharaoh at once consented to let the people go. This consideration alone unravels the mystery, and explains everything. Let it be observed that there is nothing spoken here of the eternal state of the Egyptian king; nor does anything in the whole of the subsequent account authorize us to believe that God hardened his heart against the influences of his own grace, that he might occasion him so to sin that his justice might consign him to hell. This would be such an act of flagrant injustice as we could scarcely attribute to the worst of men. He who leads another into an offense that he may have a fairer pretense to punish him for it, or brings him into such circumstances that he cannot avoid committing a capital crime, and then hangs him for it, is surely the most execrable of mortals. What then should we make of the God of justice and mercy should we attribute to him a decree, the date of which is lost in eternity, by which he has determined to cut off from the possibility of salvation millions of millions of unborn souls, and leave them under a necessity of sinning, by actually hardening their hearts against the influences of his own grace and Spirit, that he may, on the pretext of justice, consign them to endless perdition? Whatever may be pretended in behalf of such unqualified opinions, it must be evident to all who are not deeply prejudiced, that neither the justice nor the sovereignty of God can be magnified by them. See Clarke farther on Exodus 9:16 (note).

I will harden - Calamities which do not subdue the heart harden it. In the case of Pharaoh, the hardening was at once a righteous judgment, and a natural result of a long series of oppressions and cruelties.

4:21 In thy hand - in thy power: I will harden his heart - After he has frequently harden'd it himself, wilfully shutting his eyes against the light, I will at last permit Satan to harden it effectually.