Tafsir Al-Jalalayn: At-Tur, Ayah 1

And from his narration on the authority of Ibn 'Abbas that he said concerning the interpretation of Allah's saying (By the Mount (wa't-Tur)): '(By the Mount) He says: Allah swears by the mount of Zubayr and every mount is a Tur as in the Syriac and Coptic languages, but Allah means here the mount whereon Allah spoke with Moses, and this mount is called the mount of Midian or Zubayr.