"And now we must return an answer also to those who would have the God of the law to be just only, and not also good; and let us ask such in what manner they consider the heart of Pharaoh to have been hardened by God— by what acts or by what prospective arrangements. For we must observe the conception of a God who in our opinion is both just and good, but according to them only just. And let them show us how a God whom they also acknowledge to be just, can with justice cause the heart of a man to be hardened, that, in consequence of that very hardening, he may sin and be ruined. And how shall the justice of God be defended, if He Himself is the cause of the destruction of those whom, owing to their unbelief (through their being hardened), He has afterwards condemned by the authority of a judge? For why does He blame him, saying, 'But since you will not let My people go, lo, I will smite all the first-born in Egypt, even your first-born,' and whatever else was spoken through Moses by God to Pharaoh? For it behooves every one who maintains the truth of what is recorded in Scripture, and who desires to show that the God of the law and the prophets is just, to render a reason for all these things, and to show how there is in them nothing at all derogatory to the justice of God, since, although they deny His goodness, they admit that He is a just judge, and creator of the world. Different, however, is the method of our reply to those who assert that the creator of this world is a malignant being, i.e., a devil."
See Origen of Alexandria's De Principiis III.1.9