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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:18:93 –

Until, when he reached ˹a pass˺ between two mountains, he found beside them a people who could hardly understand ˹his˺ speech.  

until, when he reached between the two barriers (read al-saddayn or al-suddayn here and ˹likewise˺ further below ˹at verse 94, saddan or suddan˺) — ˹these were˺ two mountains ˹lying˺ in the remote regions beyond the land of the Turks; Alexander sealed the breach between the two, as will be described ˹below˺ — he found on this side of them, that is, in front of them, a folk that could scarcely comprehend speech, in other words, they could only understand it after much agonising (a variant reading ˹for yafqahūna, ‘comprehend’˺ has yufqihūna, ‘be understood’).
القرآن:١٨:٩٣ –

حَتَّىٰ إِذَا بَلَغَ بَيْنَ السَّدَّيْنِ وَجَدَ مِنْ دُونِهِمَا قَوْمًا لَا يَكَادُونَ يَفْقَهُونَ قَوْلًا  

{حتى إذا بلغ بين السدين} بفتح السين وضمها هنا وبعدهما جبلان بمنقطع بلاد الترك، سد الإسكندر ما بينهما كما سيأتي {وجد من دونهما} أي أمامهما {قوما لا يكادون يفقهون قولاً} أي لا يفهمونه إلا بعد بطء، وفي قراءة بضم الياء وكسر القاف.