Joseph's brothers tell their father of Joseph's request 12:63-68
12:63 When they returned to their father, they said, 'Father, we have been denied the measure. Send our brother with us and we shall receive our measure. We will indeed look after him.'
12:64 He replied, 'Am I to trust you with him as I once trusted you with his brother? Why, Allah is the Best of guardians, and He is the Most Merciful of the Merciful.'
12:65 When they opened their saddlebags, they found that their merchandise had been given back to them. 'Father,' they said 'what more do we desire? Look, our merchandise has been returned to us. We will receive provisions for our family and we will look after our brother. We shall receive an extra camel-load, that is an easy measure.'
12:66 He replied, 'I will never send him with you until you swear by Allah that you will bring him back to me, unless you are prevented.' And when they had given him their oath, he said, 'Allah is the Guardian of what we say.'
12:67 Then he said, 'My sons, do not enter from one gate. Enter through different gates. I cannot be of any help to you against Allah; judgement belongs to Allah alone. In Him I have put my trust. In Him let all put their trust.'
12:68 And when they entered from where their father had instructed them, nothing helped them against (the decree of) Allah. It was but a need in Jacob's soul which he had fulfilled. He possessed knowledge because of what We had taught him, though most people do not know.