"Say, to Allah belongs intercession entirely." That is: no one shall intercede on the Day of Resurrection except by His permission. He permits whom He wills from among the angels, the prophets, and the believers to intercede for the believers, and He accepts their intercession on their behalf.
Tafsir of Surah Az-Zumar from verse 45 to verse 48.
﴿قل لله الشَّفَاعَة جَمِيعًا﴾ أَي: لَا يشفع أحدٌ يَوْم الْقِيَامَة إِلَّا بِإِذْنِهِ , يَأْذَن لمن يَشَاء من الْمَلَائِكَة والأنبياء وَالْمُؤمنِينَ أَن يشفعوا للْمُؤْمِنين فيشفعهم فيهم.
تَفْسِير سُورَة الزمر من الْآيَة ٤٥ إِلَى آيَة ٤٨.
