"I heard Ash-Sha'bi say: 'Alqamah bin Qais forgot (and made a mistake) in his prayer, and they told him about that after he had spoken, He said: 'Is that true, O odd-eyed one?' He said: 'Yes.' So he undid his cloak, then he performed two prostrations of forgtfulness,and said: 'This is what the Messenger of Allah (ﷺ) did.' He said: And I heard Al-Hakam say: 'Alqamah had prayed five.'"
Hadith Text
"I heard Ash-Sha'bi say: 'Alqamah bin Qais forgot (and made a mistake) in his prayer, and they told him about that after he had spoken, He said: 'Is that true, O odd-eyed one?' He said: 'Yes.' So he undid his cloak, then he performed two prostrations of forgetfulness, and said: 'This is what the Messenger of Allah (ﷺ) did.' He said: And I heard Al-Hakam say: 'Alqamah had prayed five.'"
Source Reference
The Book of Forgetfulness (In Prayer)
Sunan an-Nasa'i
Sunan an-Nasa'i 1257
Scholarly Commentary
This narration demonstrates the established Sunnah of performing the two prostrations of forgetfulness (sajdat al-sahw) when a mistake occurs in prayer. Alqamah bin Qais, a prominent Tabi'i (successor), forgot during his prayer and was informed after completing it. His immediate response - verifying the information and then performing the corrective prostrations - shows the importance of rectifying prayer errors even after their completion.
The phrase "undid his cloak" indicates he prepared himself properly for the additional prostrations, treating them with the same reverence as the original prayer. His explicit statement "This is what the Messenger of Allah did" confirms this practice originates from the Prophet himself, establishing it as authoritative Sunnah.
Al-Hakam's addition that "Alqamah had prayed five" clarifies the nature of the mistake - he performed an extra rak'ah (prayer unit), making five instead of the required four for Zuhr, 'Asr, or 'Isha prayers. This specific case falls under the category of addition (ziyadah) in prayer, for which the Sunnah remedy is to perform the two prostrations of forgetfulness before the taslim (closing salutation).
Legal Rulings Derived
The two prostrations of forgetfulness are obligatory when certain errors occur in prayer.
If one adds an extra rak'ah to the prayer unintentionally, the prostrations should be performed before the final taslim.
The validity of performing sajdat al-sahw remains even if some time has passed after the prayer, as long as one has not intentionally delayed it.
The testimony of a reliable Muslim about a prayer error is sufficient grounds to perform the corrective prostrations.