Answered by Shaykh Faraz Rabbani
The Urdu manuals that were used to teach me prayer as a child did not distinguish between praying alone and in groups so I used to recite both Fatiha and a surah when praying behind an imam. Do I have to make up my prayers?
Wa Alaykum Assalam wa Rahmatullah wa Barakatuhu,
It is prohibitively disliked (makruh tahriman) and sinful for the follower to recite behind the imam in congregational prayer, whether the imam is reciting quietly or aloud. [Ibn Abidin, Radd al-Muhtar; Ibn al-Humam, Fath al-Qadir Sharh al-Hidaya]
The legal basis is that it is necessary (wajib) to repeat any prayer in which one did anything prohibitively disliked. [ibid.] This is because of the gross deficiency that entered into the performance of the prayer, not because of legal invalidity.
However, there is a dispensationmentioned by most of the great later scholars of the Hanafi school (including Ibn Nujaym, Haskafi, Shurunbulali, and Tahtawi)that it is not necessary to repeat such prayers once the time has gone out. Rather, it is recommended to do so. This is a dispensation that one can take when it comes to repeated past errors, while repenting sincerely from ones remissness.
And Allah alone gives success.
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