﴿ ذَٰلِكَ مِنْ أَنۢبَآءِ ٱلْغَيْبِ نُوحِيهِ إِلَيْكَ ۖ وَمَا كُنتَ لَدَيْهِمْ إِذْ أَجْمَعُوٓا۟ أَمْرَهُمْ وَهُمْ يَمْكُرُونَ ﴾

“THIS ACCOUNT of something that was beyond the reach of thy perception We [now] reveal unto thee, [O Prophet:] for thou wert not with Joseph's brothers when they resolved upon what they were going to do and wove their schemes [against him].”

That which is mentioned of the matter of Joseph is of the tidings the tales of the Unseen what has been hidden from you O Muhammad (s) which We reveal to you; for you were not with them with Joseph’s brothers when they agreed upon their plan to plot against him that is when they resolved upon it and schemed against him; in other words you were not present among them to know their story and so tell it to others knowledge of it has come to you through revelation.