According to Taberî, Yûsuf ordered his servants to place back the price of the grain (their capital) that they had taken from their brothers into their loads. He mentions three possibilities regarding the reason for this order: that their fathers might need money during the year of famine, that he wished to show kindness and generosity by returning their money to them without their knowledge, or that he wished to ensure that upon their return, finding the price in their loads, they would not break their promise to return.

فإن قال قائل: ولأية علة أمر يوسف فتيانه أن يجعلوا بضاعة إخوته في رحالهم؟ قيل: يحتمل ذلك أوجها: أحدها: أن يكون خشي أن لا يكون عند أبيه دراهم، إذ كانت السنة سنة جدب وقحط، فيضر أخذ ذلك منهم به

According to Zemahşerî, the word 'fityân' in the verse is the plural of 'fetâ'; the order here is directed at Yûsuf's weighing servants to place their brothers' capital back into their loads, so that the brothers would understand that it was returned to them, and also appreciate the value of generosity/munificence of having received both the price and the goods.

وهما جمع فتى ، كإخوة وإخوان في أخ ، و ( فعلة ) للقلة . و ( فعلان ) للكثرة ، أي لغلمانه الكيالين لعلهم يعرفون حق ردها وحقط التكرم بإعطاء البدلين

According to this exegete, since the word 'rihâl' expresses plurality, many people must have performed this task. The view that Yûsuf's brothers were unaware that their capital was placed in their loads is preferred; ten different views are transmitted regarding the reason for this placement (showing kindness, concern that their fathers might not have money, being generous during famine, that taking payment from those in need is base behavior, suspicion that it was placed by mistake, not imposing obligation/favor, showing that he did not wish for his brother to suffer injustice, bestowing kindness on his father, protection from highway robbers, repaying evil with good).

والرحال تفيد العدد الكثير فوجب أن يكون الذين يباشرون ذلك العمل كثيرين . المسألة الثانية : اتفق الأكثرون على أن إخوة يوسف ما كانوا عالمين بجعل البضاعة في رحالهم

Kurtubî transmits several views in this verse regarding the reason why Hz. Yûsuf had his brothers' capital (the price of wheat) placed back into their loads: the possibility that it might be lost on the road, the purpose of helping them acquire food upon their return, his disapproval of taking payment for food from his father and brothers, or wishing to make his brothers willing to return again upon seeing his generosity.

لجواز ألا تسلم في الطريق وقيل : إنما فعل ذلك ليرجعوا إذا وجدوا ذلك لعلمه أنهم لا يقبلون الطعام إلا بثمنه قيل : ليستعينوا بذلك على الرجوع لشراء الطعام وقيل : استقبح أن يأخذ من أبيه وإخوته ثمن الطعام وقيل : ليروا فضله ويرغبوا في الرجوع إليه

According to Ibn Kesîr, this text indicates that the capital (the price) that the brothers had brought to Egypt to obtain provisions was placed back into their belongings without their knowledge. In other words, they set out on their journey not knowing that this money had been returned to them.

أي التي قدموا بها ليمتاروا عوضا عنها أي في أمتعتهم من حيث لا يشعرون

According to this exegete, Yûsuf had the merchandise (its price) that his brothers had brought placed back into their loads again; this behavior was a favor to them, a display of nobility, and stemmed from concern that they might not have anything else to bring back to their father. As a difference in recitation, the reading of the word 'fityânahu' carrying a plural meaning was seen as consistent with the preceding command 'put their merchandise back in their loads,' because a separate agent was assigned for each load. The expression 'perhaps they will recognize it' refers to the brothers' realization or understanding of the necessity of this goods being returned, while 'perhaps they will return' points to the hope that this awareness will prompt them to come back again.

وإنما فعل ذلك توسيعا وتفضلا عليهم وترفعا من أن يأخذ ثمن الطعام منهم، وخوفا من أن لا يكون عند أبيه ما يرجعون به. لعلهم يعرفونها لعلهم يعرفون حق ردها.