What should one do who forgot the first tashahhud and stood for the third rak'ah?
Short answer
If he has stood fully upright he does not go back to the first tashahhud, but continues his prayer and performs the prostration of forgetfulness before the salam.
Evidence and explanation
The Shaykh cited the hadith of al-Mughirah ibn Shu'bah, may Allah be pleased with him, and determined that he continues and performs the prostration of forgetfulness before the salam.
Scholar referenced
This editorial summary is based on the original source linked below and is not presented as a verbatim quotation from the scholar.
The views of several scholars on this issue
The detail here is effective: did the worshipper remember before standing fully or after? And there are details in the ruling of the prostration of forgetfulness when returning before standing fully.
It is not enough to say 'he forgot the first tashahhud' alone: the ruling differs according to his remembering during rising or after standing upright, and according to the wording of each fatwa. We do not affirm that the limits of the detail agree among the scholars from a short summary.
An effective restriction: Ibn Baz's source mentions returning when remembering during the rising, and continuing if he began the recitation; and Ibn al-'Uthaymin's source forbids returning after standing fully. We do not fill the space between the two cases with new inference.
Shaykh Muhammad ibn Salih al-'Uthaymin, may Allah have mercy on him
If he stands fully after forgetting the first tashahhud he does not return, and leaving the tashahhud is made up by the prostration of forgetfulness before the salam.
A textual fatwa in the Shaykh's official archive- The view the scholar preferred or determined
- Detail according to the time of remembering — Shaykh Ibn al-'Uthaymin
- How the evidence is derived in his source
- He cited the hadith of al-Mughirah ibn Shu'bah, may Allah be pleased with him, and determined that one who stands fully does not return and prostrates for forgetfulness before the salam, and one who remembered before rising returns.
Shaykh 'Abd al-'Aziz ibn Baz, may Allah have mercy on him
He detailed returning if he remembers during the rising, and continuing if he does not remember until after beginning the recitation, and mentioned the prostration of forgetfulness.
A textual fatwa on the Shaykh's site- The view the scholar preferred or determined
- The detail between during the rising and beginning the recitation — Shaykh Ibn Baz
- How the evidence is derived in his source
- He mentioned the action of the Prophet ﷺ when he left the first tashahhud and made two prostrations of forgetfulness before the salam, with his detail in the cases mentioned in the question.
Shaykh Salih ibn Fawzan al-Fawzan, may Allah preserve him
He made clear in his recorded answer that whoever did not stand fully then remembers returns to the tashahhud, and whoever stood fully does not return and the prostration of forgetfulness makes it up.
A recorded answer on a channel officially attributed to the Shaykh; refer to the audio- The view the scholar preferred or determined
- An audible explanation of the issue of standing — Shaykh al-Fawzan
- How the evidence is derived in his source
- The recording referred to in the previous version needs careful audio review before extracting wordings or attributing a detailed evidence to it.
A methodological note: presenting a scholar's preference does not mean the site preferred it, and it is not right to describe it as the absolute preponderant view merely because of many agreeing. The editorial summaries and the explanation of how the evidence is derived have not yet been approved by independent Shari'ah review; read the original source in full. The details of the incident may affect the ruling.
Source
Ruling on the imam returning to the tashahhud after standing for the third rak'ah
Title of the original page (Arabic): حكم رجوع الإمام للتشهد بعد القيام للثالثة
Shaykh Muhammad ibn Salih al-‘Uthaymin, may Allah have mercy on him