It is narrated from Hazrat Farwah bin Amr Bayazi that the Messenger of Allah, peace and blessings be upon him, came to the people while they were praying. Their voices were raised due to the recitation of the Word of Allah. So the Prophet, peace and blessings be upon him, said: "The one who is praying is whispering to his Lord, so he should understand and whisper, and one of you should not raise his voice over another in the Qur'an."