Genesis 20:2

And he said of Sarah his wife, She is my sister. So Abimelech king of Gerar sent, and took her. Why Abraham said this about Sarah, and whence it should be believed that she, although taken into the king's house, was by no means touched by the king's embrace, has already been said above, where in a similar manner she was taken by Pharaoh but returned to her husband at the command of the Lord. It follows.

I think, therefore, that Sarah, who is interpreted 'princess' or 'one exercising rule', holds the figure of ἀρετή, which is the virtue of the soul. This virtue, then, is joined and cleaves to a wise and faithful man, just as also that wise man who said concerning wisdom: "I sought to bring her to me as my bride." Therefore for this reason it is said by God to Abraham: "in all things whatsoever Sarah shall say to you, hearken to her voice." Which surely is not fittingly said in a bodily marriage, since indeed that sentence was uttered by divine authority which says to the woman concerning the man: "your turning shall be to him, and he shall have dominion over you." If, then, the man is said to be lord of the woman, how could it in turn be said to the man: "in all things whatsoever Sarah shall say to you, hearken to her voice"? If, then, anyone has taken virtue to himself in marriage, let him hearken to her voice in all things in which she gives him counsel. Therefore Abraham no longer wishes his wife to be called virtue. For so long as virtue is called a wife, she is one's own and can be shared with no one. And it is fitting that, until we come to perfection, the virtue of the soul should be within us and be our own; but when we have come to perfection, so that we are fit to teach others also, then we no longer shut virtue up within our bosom as a wife, but join her also, as a sister, to others who wish for her. To these, finally, who are perfect, the divine word will say: "say that wisdom is your sister." According to this, therefore, Abraham also said that Sarah was his sister. He permits, then, as one now perfect, that whoever wishes may have virtue.

"Abraham moved from there to the southern land," the text goes on, "and dwelt between Kadesh and Shur, sojourning at Gerar." Moved on from where? From the place where he was camped, where he was given the privilege of hosting the Lord of all with the angels. Moving from there, the text says, "he sojourned in Gerar." Notice the life of these good people, how restrained and austere it was, how they shifted place with ease and conducted their life like pilgrims or nomads, pitching their tent at one time in this place, at another in that, as though living in a strange land. They are unlike us, who live in a strange land as though in our home country, erecting extravagant mansions, porches and covered walks, possessing land, building baths and countless other luxuries.By contrast see the good man holding all his possessions in his household and flocks alone. [He is] never staying in one place but at one time pitching his tent in Bethel, at another by the oak of Mamre, at another going down to Egypt and now camping at Gerar, submitting to all this with ease and giving clear evidence in every way of gratitude to his own Lord. Despite such wonderful promises and guarantees given him by God, he saw himself beset by such imposing difficulties and encountering such varied and differing trials. Yet he stood unshaken like some piece of steel, showing his godly attitude and proving no less resolute in any of the problems surrounding him. See in the present instance too, dearly beloved, the kind of trial that befell him at Gerar and the wonderful caliber of the just man's virtue. What everyone else found unbearable and could not bring themselves to accept he put up with without complaint and without demanding from the Lord explanation of what happened, as many people do, even though weighed down with countless burdens of sin. When they encounter some difficulties, they become meddlesome and inquisitive, saying, "Why has this or that happened?" The just man, on the contrary, didn't behave like that; hence he enjoyed greater favor from on high. This, after all, is truly the mark of a dutiful servant, not to pry into reasons for what is done by the master but to accept everything in silence and with deep thanks.