What is the obligation upon the follower if the Imam commits an act of forgetfulness?

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The follower must follow the Imam in the prostration of forgetfulness whether the Imam's error occurred concurrently with the follower's or if the Imam erred alone. Ibn al-Mundhir stated there is consensus among the scholars he is aware of regarding this. Ishaq mentioned consensus among scholars that the follower must follow the Imam in prostration, regardless of whether the prostration occurs before or after the conclusion of the prayer (taslīm). This is based on the command, 'When he prostrates, then prostrate,' and the narration of Ibn 'Umar that the Imam is made to be followed. The prostration is an integral part of the prayer, thus demanding adherence, similar to what occurs before the conclusion.