15 hereby ye shall be proved: by the life of Pharaoh ye shall not go forth hence, except your youngest brother come hither. 16 Send one of you, and let him fetch your brother, and ye shall be bound, that your words may be proved, whether there be truth in you: or else by the life of Pharaoh surely ye are spies.
Matthew Henry's Commentary on Genesis 42:15-16
Commentary on Genesis 42:7-20
(Read Genesis 42:7-20)
Joseph was hard upon his brethren, not from a spirit of revenge, but to bring them to repentance. Not seeing his brother Benjamin, he suspected that they had made away with him, and he gave them occasion to speak of their father and brother. God, in his providence, sometimes seems harsh with those he loves, and speaks roughly to those for whom yet he has great mercy in store. Joseph settled at last, that one of them should be left, and the rest go home and fetch Benjamin. It was a very encouraging word he said to them, "I fear God;" as if he had said, You may be assured I will do you no wrong; I dare not, for I know there is one higher than I. With those that fear God, we may expect fair dealing.