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After this verse was revealed, whenever Omar bin Al-Khattab wanted to speak to the Prophet (PBUH), he would talk as if he was whispering. The Prophet would hardly hear him and he would have to ask what Umar just said.
يا ايها الذين امنوا لا ترفعوا اصواتكم فوق صوت النبي و '
"O you who believe, do not raise your voices above the voice of the Prophet or be loud to him in speech like the loudness of some of you to others, lest your deeds become worthless while you perceive not.