Joseph shifts his strategy regarding his brothers, abandoning his original idea of imprisoning the entire group and dispatching only one. Instead, he introduces a new arrangement that serves as a strict test of their loyalty while also showing concern for their starving families back in Canaan.
By challenging them to prove their honesty, Joseph presents a twofold test. On a practical level, their willingness to leave one brother behind as a hostage demonstrates their credibility. If they were actually spies with no intention of returning, no brother would agree to remain, knowing it would mean certain execution [מלבי״ם]. Psychologically, if they are truly truthful, they will not be afraid to leave someone behind, confident that their innocence will eventually be proven and he will remain unharmed [אור החיים]. A different perspective views their honesty as a reflection of them being decent family men. Joseph recognizes that if they indeed have dependents, keeping them all in custody would cause their wives and children to starve, prompting him to allow the majority to go home [העמק דבר, ביאור שטיינזלץ].
To guarantee their return, Joseph demands that one specific brother remain incarcerated. This choice is not random; it targets Simeon, who had been dominant and cruel during Joseph's sale [הכתב והקבלה]. Furthermore, singling out one brother is designed to awaken their guilty consciences, reminding them of that other single brother they had once thrown into a pit [קונטרס חיבה יתירה]. On a practical level, keeping a hostage prevents deception. Joseph anticipates the possibility that the brothers might purchase a random youth from the market and present him as Benjamin. The brother left in prison would be forced to identify the boy, thereby exposing any fraud [פרדס יוסף].
The condition that the hostage will be bound in their own place of custody seems unusual, as the prison belongs to the Egyptian government, not the brothers. The primary approach among commentators is that this simply refers to the facility where the brothers are already being held [רש״י, מזרחי, גור אריה]. However, this phrasing also carries deeper messages. Joseph wants to reassure the brother staying behind that he will not be transferred to a severe dungeon or put in strict isolation. Instead, he will remain in the familiar conditions they all just experienced together and proved they could survive [דברי דוד, קונטרס חיבה יתירה]. Emotionally, it signals to the departing brothers that even when they return home, their consciences will torment them. They will feel as though they are still sitting in the guardhouse alongside their captive brother [פרדס יוסף].
Once the hostage arrangement is set, Joseph directs the brothers to transport the purchased grain away to their father's house in Canaan to satisfy the hunger of their households [רד״ק, שד״ל, רש״י, מזרחי]. The specific instruction to simply break their hunger carries a broader moral lesson. It teaches that a person should eat only enough to satisfy their hunger and sustain their body, avoiding excessive desires for food and drink. Distancing oneself from worldly cravings is considered a fundamental aspect of fearing God [רבנו בחיי].