´Ibn Abbas said:` “When the Quran was being revealed to the Messenger of Allah, he would move his tongue in attempt to memorize it. So Allah, Blessed is He and Most High, revealed: Move not your tongue concerning it to make haste therewith.” He said: “So he would move his two lips.” And Sufyan (a sub-narrator) would move his two lips.
Hadith Referenceسنن ترمذي / كتاب تفسير القرآن عن رسول الله صلى الله عليه وسلم / 3329