(O ye who believe!) This was revealed about Thabit Ibn Qays Ibn Shammas who raised his voice in the presence of the Messenger of Allah (pbuh) upon the visit of the delegation of Banu Tamim. And so Allah forbade him from doing so. Allah said: O you who believe in Muhammad (pbuh) and the Qur'an; in reference to Thabit, (Lift not up your voices above the voice of the Prophet) Allah bless him and give him peace, nor insist in talking when the Prophet (pbuh) is talking, (nor shout when speaking to him) nor call him by his first name (as ye shout one to another) as you would do with one another; rather you should reverence and honour him and address him by: “O Prophet of Allah” or “O Messenger of Allah” or “O Abu'l-Qasim”, (lest your works be rendered vain while ye perceive not) lest your good works be nullified for failing to observe propriety and reverence towards the Prophet (pbuh) while not knowing that your works are nullified.