فلما جهزهم بجهازهم جعل السقاية في رحل أخيه ثم أذن مؤذن أيتها (12:70) بالانجليزي

(12:70) While Joseph was arranging for the loading of the packs of his brothers, he put his cup in the pack of his own brother. *56 Afterwards a herald shouted, "Ho, cameleers ! you are thieves. ,, *57

Tafseer Abu-al-A'la Maududi

Page 244 English Traditional

*56) In all probability, Prophet Joseph put the cup in his brother's pack with his knowledge and consent, as may be inferred from the preceding verse. Obviously. Prophet Joseph desired to free his brother from the oppression of the cruel step-brothers and he himself was reluctant to go back with them. But this could not be done directly and openly without disclosing his own identity, which was not then expedient under the circumstances. Therefore both the brothers might have thought out this plan, though this would have put the younger brother in an embarrassing situation for the time being because of his involvement in a case of theft. But they had adopted this plan because afterwards both the brothers could clear it easily by disclosing the real matter.
*57) There is nothing in this verse nor in the succeeding verses to show that Prophet Joseph took his servants in his confidence in regard to this matter, and instructed them to bring a false accusation against the travellers. The simple explanation of the incident may be this. The cup might have been quietly and secretly put in the pack. Afterwards when the servants did not find it, they might have come to the inevitable conclusion that it must have been stolen by the travellers who were staying there.