Genesis 42:35

And it came to pass, as they emptied their sacks, that, behold, every man's bundle of money was in his sack; and when both they and their father saw the bundles of money, the little sacks of silver with which they thought they had paid their grain, they were afraid. Surely the ruler of Egypt would now regard them as thieves. This fear was to have a wholesome effect, for it was intended to soften the hard hearts still more, just as the Lord even after conversion exhibits our sinfulness to us, in order that our knowledge of His grace may be all the sweeter.