What is the ruling on the prayer of one who led the congregational prayer for two rak'ahs, then recited the tashahhud, then sat for the tashahhud in the third rak'ah, and then stood up after being alerted to complete the fourth rak'ah, then performed the two prostrations of forgetfulness (sujood al-sahw) before the tasleem? And does the ruling differ according to the different schools of thought?

An inadvertent addition during prayer—such as sitting in the third rak'ah—requires a prostration of forgetfulness (sujud al-sahw) after the tasleem, according to the Maliki school. This was also the old opinion of Imam Shafi'i. However, Imam Shafi'i's new opinion (in his new madhhab) is that all prostrations of forgetfulness are performed before the tasleem. Conversely, the relied-upon view among the Hanafis is that all prostrations of forgetfulness are performed after the tasleem, based on the statement of Al-Sarakhsi: "And indeed, the prostration of forgetfulness becomes obligatory by delaying a pillar from its place, and it is performed after the tasleem according to us."