The verses appearing above carry the remaining segment of the event, that is, when the brothers of Yusuf (علیہ السلام) returned home with food-grains from Egypt, they told their father about what had happened there, specially about the condition imposed by the ` Aziz of Misr that they would receive food grains in the future only if they would bring their younger brother with them. So they requested their father to let Benyamin also accompany them in order that they may receive food grains in the future as well. Then, they would be there to protect this brother of theirs at its best with assurance that they would see to it that he faces no inconvenience during the trip.
Their father asked them if they wanted him to trust them with Benyamin as he had done before with their brother, Yusuf (علیہ السلام) . The drive of his remark makes it obvious that he did not trust their word. He had trusted them once, and suffered - for they had promised in the same words spoken earlier that they would guard him.
This much was an answer to what they had said. But, he had the need of the family in sight, and because he was blessed with the quality of trust in the Divine dispension of matters, he talked about the reality as he knew it saying, in effect, that man has no control over his gain or loss unless Allah Ta ala Himself so wills. And when He wills it, it cannot be diverted or averted by anyone. Therefore, it is incorrect to place one's trust in the created beings of Allah in this matter and equally inappropriate is the dependence on their complaints to settle it.