Origen of Alexandria : Yet Pharaoh too once wished to take Sarah, but he did not wish it "with a clean heart"; and virtue cannot come together with anything except purity of heart. Therefore, then, Scripture reports that "the Lord afflicted Pharaoh with great and grievous afflictions." For virtue could not dwell with an exterminator — for this is what Pharaoh means in our tongue. But let us see what Abimelech said to the Lord. "You know, Lord," he says, "that I have done this with a clean heart." This Abimelech acts far otherwise than Pharaoh. He is not so ignorant and foul, but knows that he must prepare a "clean heart" for virtue. And because with a pure heart he wished to receive virtue, therefore God heals him when Abraham prays for him. And not only him, but He heals his maidservants too. — HOMILIES ON Genesis 6.2