"And mention the brother of 'Ad," meaning: Hud. He was their brother by lineage, not their brother in faith. "When he warned his people at the Al-Ahqaf," and they were their dwellings.
Muhammad said: Al-Ahqaf in the language, its singular is: hiqf, which is that which is elevated and elongated from the sand dunes. It has been said: that Al-Ahqaf here refers to a mountain in the Levant.
"And the warners have passed away before him and after him." This is the beginning of a new sentence, wherein Allah informs that the warners had already passed away before Hud, meaning: prior to him, "and after him," meaning:
﴿وَاذْكُر أَخا عَاد﴾ يَعْنِي: هودًا؛ أخوهم فِي النّسَب، وَلَيْسَ بأخيهم فِي الدّين ﴿إِذْ أنذر قومه بالأحقاف﴾ وَكَانَت مَنَازِلهمْ.
قَالَ محمدٌ: الأحقافُ فِي اللُّغَة وَاحِدهَا: حِقْفٌ، وَهُوَ من الرمل مَا أشرف من كثبانه واستطال، وَقد قيل: إِن الْأَحْقَاف هَا هُنَا: جبلٌ بِالشَّام.
﴿وَقَدْ خَلَتِ النُّذُرُ مِنْ بَيْنِ يَدَيْهِ وَمِنْ خَلْفِهِ﴾ وَهُوَ بَدْء كَلَام مُسْتَقْبل، يخبر اللَّه أَن النّذر قد مَضَت من بَين يَدي هود؛ أَي: من قبله ﴿وَمن خَلفه﴾ أَي:
