This Story is a Revelation from Allah

Allah narrated to Muhammad ﷺ, the story of Yusuf and his brothers and how Allah raised him over them, giving him the better end, triumph, the sovereignty and wisdom (i.e., prophethood), even though they tried to harm and kill him. Allah said, `This and similar stories are part of the unseen incidents of the past, O Muhammad,

نُوحِيهِ إِلَيْكَ

After that it was said: وَمَا تَسْأَلُهُمْ عَلَيْهِ مِنْ أَجْرٍ‌ ۚ إِنْ هُوَ إِلَّا ذِكْرٌ‌ لِّلْعَالَمِين ، that is, ` your mission is to tell them the truth and call 'them to the straight path. For this you do not ask them to give you something in return - which could have caused them to find it difficult to listen to him or follow him. In fact, what you are telling them is for their own good. It is only an advice to heed to and a lesson to learn from. And it is for everyone. The text here also carries a hint to the effect: When the purpose behind your effort is no worldly gain, in fact it is nothing but the reward of the Hereafter and the betterment of your people, then, that purpose of yours already stands achieved. Why would you then grieve over it?