Genesis 44:5

5.Whereby indeed, he divineth (171) This clause is variously expounded. For some take it as if Joseph pretended that he consulted soothsayers in order to find out the thief. Others translate it, “by which he has tried you, or searched you out;” others, that the stolen cup had given Joseph an unfavorable omen. The genuine sense seems to me to be this: that he had used the cup for divinations and for magical arts; which, however, we have said, he feigned, for the sake of aggravating the charge brought against them. But the question arises, how does Joseph allow himself to resort to such an expedient? For besides that it was sinful for him to profess augury; he vainly and unworthily transfers to imaginary deities the honor due only to divine grace. On a former occasion, he had declared that he was unable to interpret dreams, except so far as God should suggest the truth to him; now he obscures this entire ascription of praise to divine grace; and what is worse, by boasting that he is a magician rather than proclaiming himself a prophet of God, he impiously profanes the gift of the Holy Spirit. Doubtless, in this dissimulation, it is not to be denied, that he sinned grievously. Yet I think that, at the first, he had endeavored, by all means in his power, to give unto God his due honor; and it was not his fault that the whole kingdom of Egypt was ignorant of the fact that he excelled in skill, not by magical arts, but by a celestial gift. But since the Egyptians were accustomed to the illusions of the magicians, this ancient error so prevailed, that they believed Joseph to be one of them; and I do not doubt that this rumor was spread abroad among the people, although contrary to his desire and intention. Now Joseph, in feigning himself to be a stranger to his brethren, combines many falsehoods in one, and takes advantage of the prevailing vulgar opinion that he used auguries. Whence we gather, that when any one swerves from the right line, he is prone to fall into various sins. Wherefore, being warned by this example, let us learn to allow ourselves in nothing except what we know is approved by God. But especially must we avoid all dissimulation, which either produces or confirms mischievous impostures. Besides, we are warned, that it is not sufficient for any one to oppose a prevailing vice for a time; unless he add constancy of resistance, even though the evil may become excessive. For he discharges his duty very defectively, who, having once testified that he is displeased with what is evil, afterwards, by his silence or connivance, gives it a kind of assent.