standing fully upright, he must not return to it. Should he go back knowing that this is impermissible, the prayer is invalid; if he returns out of forgetfulness, the prayer is not invalidated but he must perform the prostration of forgetfulness, and the same ruling holds if he was unaware of the prohibition, according to the soundest view. For the follower, however, going back in order to stay in step with the imam is permissible, according to the soundest view.
I say: the sounder opinion is that this return is obligatory—Allah knows best.
If he remembers the omitted tashahhud before he has straightened up, he should sit back for it, and he must perform the prostration of forgetfulness if, at that point, he was nearer to standing than to sitting. If he rose intentionally and then went back, the prayer is invalid whenever he had been closer to standing than to sitting.
If he forgets the qunūt and recalls it while in prostration, he does not go back for it; but if he remembers before prostrating, he should return to it and then prostrate for forgetfulness, provided he had reached the level of bowing.
If he is unsure whether he has omitted one of the two prostrations or committed a forbidden act, no prostration is required. Yet if he has lapsed and now doubts whether he has already performed the prostration of forgetfulness, he must perform it. Should he be uncertain whether he has prayed three or four rak‘ahs, he adds one rak‘ah and prostrates; the sounder view is that he still prostrates even if his doubt clears before saying salām. The same rule applies to anything he performs while uncertain and that might turn out to have been superfluous. Whatever must be performed in every case does not call for prostration once the doubt has been removed. For example, if he doubts in the third rak‘ah—“Is this the third or the fourth?”—and then remembers while still in that rak‘ah, he does not prostrate; but if the doubt arises in the fourth, he does prostrate.
If, after giving salām, he doubts that he has left out an obligation, the doubt has no effect according to the well-known view.
Any forgetfulness that befalls the follower while he is behind the imam is borne by the imam. Thus, if he mistakenly thinks the imam has ended the prayer and therefore says salām, but then discovers otherwise, he resumes with the imam when the imam actually finishes, and no prostration is required. If, during his own tashahhud, he realises that he has omitted a pillar other than the intention or the opening takbīr, he should, after the imam’s salām, stand to make up the missed rak‘ah and no prostration is prescribed. Forgetfulness occurring after his own salām is not covered by the imam; so if a late-comer finishes with the imam’s salām, he must complete what he missed and then prostrate.
The late-comer is also affected by the imam’s forgetfulness: if the imam prostrates, he must follow; if the imam does not, then the follower prostrates on his own, according to the authoritative text. If a late-comer joins an imam who commits a lapse after the late-comer has joined him—and, in the soundest opinion, even if the lapse occurred before the late-comer joined—the correct ruling is that he prostrates with the imam and then again at the end of his own prayer; but if the imam omits the prostration, the follower must perform it at the end of his own prayer, according to the explicit text.
No matter how many causes of forgetfulness exist, the prostration consists of two prostrations identical to those of the prayer itself. According to Imām al-Shāfiʿī’s new position, their proper place is between the tashahhud and the salām. If he deliberately gives salām first, the prostration is missed in the soundest view; if he forgets and a long interval passes, it is missed according to the new position—otherwise not, in line with the explicit text. Once he performs the prostration, he is considered to have returned to the prayer, according to the soundest view.
If the Friday-prayer imam lapses and the congregation prostrates with him, only to discover that the Friday prayer has been missed, they must complete the prayer as Ẓuhr and then prostrate. And if someone assumes he has erred and therefore prostrates, only to find that no error had occurred, he must prostrate again according to the soundest view.