Remembrance 1 from Chapter 45
Invoking blessings upon the messenger of Allah after the tashahhud

Allāhumma ṣalli ‘alā Muḥammadin ‘Abdika wa Rasūlika-n-Nabiyyi-l-ummyyi, wa ‘alā āli Muḥammadin wa azwājihi wa dhurriyyatih, kamā ṣallayta ‘alā Ibrāhīm wa ‘alā āli Ibrāhīm, wa bārik ‘alā Muḥammadi-n-Nabiyyi-l-ummiyyi, wa ‘alā āli Muḥammadin wa azwājihi wa dhurriyyatih, kamā bārakta ‘alā Ibrāhīma wa ‘alā āli Ibrāhīm, fi-l-‘ālamīna, innaka Ḥamīdun Majīd.
KNOW THAT TO pray for blessings upon the Messenger of Allah
after the last tashahhud is wājib according to ash-Shāfi‘ī. If one leaves it out, his ṣalāh is invalid. It is not wājib to pray for blessings upon the family of the Messenger of Allah
in it, but it is mustaḥabb. The best salutation on the Prophet
is to say: O Allah, send salutations upon Muḥammad, Your servant and Messenger, the unlettered Prophet, and upon the family of Muḥammad, as You sent salutations upon Ibrāhīm and the family of Ibrāhīm. And bless Muḥammad, the unlettered Prophet, and the family of Muḥammad, as You blessed Ibrāhīm and the family of Ibrāhīm in [all] the worlds. Truly You are most Praiseworthy, most Majestic.