Irenaeus of Lyons · a new plain-English translation from the original language
In what way God made Pharaoh's heart obstinate, and the hearts of his servants as well. "The Lord made Pharaoh's heart obstinate, and the hearts of his servants," so they claim. Yet those who bring this accusation fail to read, in the Gospel, the passage where the disciples questioned the Lord, "Why do you address them in parables?" and he replied: "To you it has been granted to know the secret of the kingdom, but to those others I speak in parables, so that looking they will not perceive, and listening they will not comprehend or grasp the meaning — so that what Isaiah foretold about them would come to pass, namely: The heart of this people has grown thick, their ears are stopped, and their eyes shut; yet your eyes are blessed, since they perceive what you perceive, and your ears, since they hear what you hear." For it is the very same God who casts darkness over those who refuse belief and count him as nothing — much as the sun, itself his creation, darkens the vision of those whose eyes, weakened, cannot bear its brightness — whereas to such as trust him and walk in his way he supplies a richer, deeper light for the mind. Along these same lines the Apostle likewise states, writing to the Corinthians a second time: "In whose case the god ruling this present age has darkened the thinking of those without faith, so that the radiance of Christ's glorious gospel might not dawn upon them." And once more, in his epistle to the Romans: "And just as they refused to keep God present in their understanding, God gave them over to a worthless mind, to carry out things unfitting." And in his second letter to the Thessalonians he states outright, referring to the Antichrist: "And so God will dispatch to them a deluding power, so that they will put faith in a falsehood — so that every one might be condemned who refused to trust what is true and instead consented to wrongdoing."
If, then, even now, as many as God — who foreknows all things — knows will never believe, he hands over to their own unbelief, and turns his face away from such people, leaving them in the darkness which they themselves have chosen, what wonder is it if, at that time too, he handed Pharaoh over to his own unbelief, along with those who were with him, knowing that he would never believe? As the Word said of the burning bush to Moses: "But I am aware that Egypt's king will not release you, except under compulsion of a mighty hand." And by the same reasoning that the Lord spoke in parables and brought blindness upon Israel, so that looking they would fail to perceive — knowing their unbelief in advance — by that same reasoning he also made Pharaoh's heart obstinate, so that, though he perceived that it was God's own finger guiding the people's departure, he would not believe, but would be plunged into the sea of his own unbelief, supposing that their departure came about through magical working, and that it was not by the power of God that the Red Sea provided a passage for the people, but that it simply happened to be so by nature.