His saying: "By the Tur (Mount)". The Tur: the mountain.
Muhammad said: It is narrated from al-Hasan that he said: Every mountain is called a Tur.
قَوْله: ﴿وَالطور﴾ الطُّور: الْجَبَل.
قَالَ محمدٌ: رُوِيَ عَن الْحسن أَنه قَالَ: كل جبل يدعى طوراً.