"Allah has certainly conferred a favor upon the believers when He sent among them a Messenger from themselves, reciting to them His verses and purifying them"—meaning: He makes them righteous. "And teaching them the Book"—the Qur'an—"and the Wisdom"—the Sunnah—"although they had been, before"—before the Prophet, peace be upon him, came to them—"in clear error"—evident.
﴿لَقَدْ مَنَّ اللَّهُ عَلَى الْمُؤْمِنِينَ إِذْ بَعَثَ فِيهِمْ رَسُولا مِنْ أَنْفُسِهِمْ يَتْلُو عَلَيْهِمْ آيَاتِهِ وَيُزَكِّيهِمْ﴾ يَعْنِي: يصلحهم. ﴿وَيُعلمهُم الْكتاب﴾ الْقُرْآن ﴿وَالْحكمَة﴾ السّنة ﴿وَإِنْ كَانُوا مِنْ قَبْلُ﴾ أَن يَأْتِيهم النَّبِي عليه السلام ﴿لفي ضلال مُبين﴾ بَين.