﴿ لَا تُحَرِّكْ بِهِۦ لِسَانَكَ لِتَعْجَلَ بِهِۦٓ ﴾

“MOVE NOT thy tongue in haste, [repeating the words of the revelation:]”

(Stir not thy tongue) to read the Qur'an, O Muhammad, (herewith to hasten it) to hasten the recitation of the Qur'an before Gabriel finishes reciting it to you. This is because the Prophet (pbuh) used to repeat whatever revelations of the Qur'an Gabriel brought down to him before the latter finished a sentence of the Qur'an, out of fear of forgetting what was revealed to him. Allah warned him against doing so.