Answered by Shaykh Faraz Rabbani
I understand that one does not do the forgetful prostration behind the imam for one’s own mistakes but what if one recites behind the imam? 1 – What should one do if one purposely recites behind the imam. Forgetful prostration, repetition afterwards, or nothing? 2 – What should one do if one mistakenly recites (more than a couple of words) behind the imam (and realizes the during the prayer). Forgetful prostration, repetition afterwards, or nothing?
Walaikum assalam wa rahmatullah,
I pray that this finds you well, and in the best of health and spirits. May Allah grant you all good and success in this life and the next.
[1] If one forgetfully leaves a necessary (wajib) action or performs a prohibitively disliked action behind the imam, one isn’t responsible for “compensating” for this in any way.
[2] If one deliberately makes the above errors, then one was sinful, and must (a) repent from the sin; and (b) repeat the prayer–though one completes one’s prayer behind the imam and doesn’t break it.
[3] If one deliberately recited the Fatiha behind the imam following the position of a Hanafi scholar who says this, then one wouldn’t repeat such a prayer–even though it is not the relied-upon position of the school, because a minority of recognized Hanafis have said so.
[4] However, if one deliberately recited behind the Fatiha behind the imam otherwise, then it would follow the fiqh of leaving a necessary (wajib) action or performing a prohibitively disliked action–as explained above.
[5] Please search SunniPath Answers (http://qa.sunnipath.com) for related answers.
Leaving a necessary action in prayer
Does reciting behind the imam invalidate prayer?
The Rulings of the Sacred Law
And Allah alone gives success.
Faraz Rabbani