Allah the Almighty said: And Joseph's brethren came and they entered unto him, and he recognized them, but they recognized him not. And when he had furnished them forth with provisions (according to their need), he said: "Bring me a brother of yours from your father; (he meant Benjamin). See you not that I give full measure, and that I am the best of the hosts? But if you bring him not to me, there shall be no measure (of corn) for you with me, nor shall you come near me."
They said: "We shall try to get permission (for him) from his father, and verily, we shall do it."
And (Joseph) told his servants to put their money (with which they had bought the corn) into their bags, so that they might know it when they go back to their people, in order that they might come back. Surah 12: 58-62