Genesis 42:18 - Joseph Benson’s Commentary on the Old and New Testaments

For I fear God This was a very encouraging word unto them. It is as if he had said, You may assure yourselves I will do you no wrong; I dare not, for I know that, as high as I am, there is one higher than I. With those that fear God we have reason to expect fair dealing: the fear of God will be a check upon those that are in power, to restrain them from abusing their power to oppression and tyranny.