Is the sitting for the first Tashahhud (Testimony of Faith) and the recitation within it obligatory in Maghrib or four-Rak'ah prayers for one who missed the beginning?

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The sitting for the *Tashahhud* and the recitation within it after the first two Rak'ah are established without dispute, having been transmitted continuously from the Prophet (peace be upon him) to later generations, and observed by the Ummah in their prayers. According to one narration, these two acts are obligatory (*Wajib*) in the Maghrib and four-Rak'ah prayers. This view is adopted by Al-Layth and Ishaq. The evidence is that the Prophet (peace be upon him) performed it, maintained the practice, and commanded it in the hadith of Ibn Abbas, where he instructed to say, 'Say: All compliments are for Allah,' and performed the prostration of forgetfulness (*Sujud As-Sahw*) when he forgot it. Furthermore, since the Prophet (peace be upon him) commanded, 'Pray as you have seen me praying,' and since this act is substituted by the prostration of forgetfulness, it resembles the compensations (*Jibranat*) of Hajj which are compensated with blood, unlike mere Sunnahs. It is also argued that this is one of the two *Tashahhuds*, thus it must be obligatory like the other.