Source: Fatāwā Muḥammadīyah, Vol. 1, p. 345
Question:
In a loud (jahri) prayer, when the Imām recites and the followers hear the name of the Messenger of Allah ﷺ, is it permissible for them to say ṣallallāhu ʿalayhi wa sallam?
Answer:
Al-ḥamdu lillāh, waṣ-ṣalātu wa-s-salāmu ʿalā Rasūlillāh, ammā baʿd:
◈ Although, to my knowledge, there is no specific ḥadīth regarding saying ṣallallāhu ʿalayhi wa sallam at this particular moment,
◈ Based on the general evidences, it is permissible to do so.
هٰذا ما عندي والله أعلم بالصواب
