"It is He who has sent among the unlettered"—the Arabs—"a Messenger from among themselves." They were unlettered, having no book from Allah as the People of the Book had, although they used to write with their own hands. "Reciting to them His verses"—the Quran—"and purifying them, and teaching them the Book and the Wisdom." Qatada’s interpretation: The Book is the Quran, the Wisdom is the Sunnah, and purification (al-zakāh) is righteous action. "And although they were, before"—he came to them—"in clear error," manifest.
﴿هُوَ الَّذِي بَعَثَ فِي الأُمِّيِّينَ﴾ الْعَرَب ﴿رَسُولا مِنْهُم﴾ كَانُوا أُمِّيين لَيْسَ عِنْدهم كتابٌ من عِنْد اللَّه كَمَا مَعَ أهل الْكتاب، وَقد كَانُوا يخطون بِأَيْدِيهِم ﴿يَتْلُو عَلَيْهِم آيَاته﴾ الْقُرْآن ﴿وَيُزَكِّيهِمْ وَيُعَلِّمُهُمُ الْكِتَابَ وَالْحِكْمَةَ﴾ تَفْسِير قَتَادَة: الْكتاب: الْقُرْآن، وَالْحكمَة: السُّنَّة، وَالزَّكَاة: الْعَمَل الصَّالح ﴿وَإِنْ كَانُوا من قبل﴾ أَن يَأْتِيهم مُحَمَّد ﴿لَفِي ضَلالٍ مُبين﴾ بَين