the prostrations of forgetfulness. Some do not require the prostrations of forgetfulness, while others are remedied by them. It is also clear that the reported saying of the Prophet (peace and blessings be upon him), “For every lapse there are two prostrations,” is not unrestricted in scope. Rather, it refers to Sunnah practices, not obligatory elements or recommended acts: omission of an obligatory element cannot be remedied by the prostrations of forgetfulness, while omission of a recommended act does not require them.

Section

Prayer consists of words and actions. All its physical actions are obligatory except three: raising the hands at the opening takbīr, turning to the right when giving the closing salutation, and the middle sitting. Rising from bowing is also excepted, since some hold it to be obligatory, because bowing is not complete without it, while others hold it to be a Sunnah practice. All the verbal elements of prayer are either Sunnah practices or recommended acts, except three: the opening takbīr, reciting al-Fātihah, and the closing salutation. There are differences of opinion concerning these matters, as we have explained for each in its appropriate place. Success comes only through Allah.

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Categories of Forgetfulness in Prayer

Forgetfulness in prayer falls into two categories: a lapse of which one is certain and a lapse about which one is doubtful. A lapse of which one is certain falls into two categories: an addition and an omission. Likewise, a lapse about which one is doubtful [also falls into two categories: an addition and an omission]. These make four categories. Within a single prayer, one may also be certain of both an addition and an omission, doubtful about both, doubtful about an addition but certain of an omission, or certain of an addition but doubtful about an omission. These complete the eight categories.

Section

As for a lapse involving an addition, it takes one of two forms: the first concerns physical actions,