Fatwa ID: 04429
Answered by: Alimah Sumeyye Sofu
When we are praying as a follower and the Imam is reciting in a loud voice (like salatul maghrib, fajr or isha) what are we supposed to do? Do we also recite in a low voice or should we keep quiet and listen to the Imam's recitation?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
You should keep silent and listen to the Imam. Do not recite anything.
Allah (SWT) says in the Holy Qur'an: “When the Qur’ān is recited, listen to it and be silent, so that you may be blessed.” (Surah Al-A'raf 204)
According to the Hanafi Fiqh, the follower remains silent in all five salaah when it is performed behind an Imam.
It was narrated that Jabir (r.a) said: "The Messenger of Allah (saw) said: 'Whoever has an Imam, the recitation of the Imam is his recitation." 
It is also narrated that Ibn Ukaimah (r.a) said: “I heard Abu Hurairah say:” The Prophet (saw) led his companions in prayer, we think it was the Subh. He said:” Did anyone among you recite?” A man said: “I did.” He said: “I was saying to myself, what is wrong with me that someone is fighting to wrest the Quran from me?” 
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Written by Alimah Sumeyye Sofu
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham