I add: Our copy of Fath al-Bari likewise reads “Saʿid b. Sulayman,” which is probably a copyist’s or printer’s slip. In light of what has been said, you can see that al-Sakhawi’s statement in al-Hirz al-Maniʿ (17): “A hasan hadith whose transmitters are those of the Sahih,” is inaccurate—the hadith is not hasan, nor are all its transmitters the men of the Sahih. Take heed and do not be misled. For this reason Abu Bakr Ibn al-Arabi said in ʿAridat al-Ahwadhi, his commentary on al-Tirmidhi (2/271): “Beware, beware of paying attention to what Ibn Abi Zayd mentioned—namely, adding to the salat upon the Prophet the words, ‘and have mercy upon Muhammad.’ Such an addition borders on bidʿa (reprehensible innovation), for the Prophet ﷺ taught the formula by revelation; adding to it implies finding it deficient and ‘correcting’ it. It is not permissible to add even a single letter to what the Prophet ﷺ prescribed, though one may invoke mercy for the Prophet at any other time.” Some have tried to rebut him with this very hadith of Abu Hurayra, but you have seen that it is weak and therefore unacceptable as evidence—especially when it contradicts an agreed-upon principle expressed in his ﷺ saying: “Whoever performs an act not in accord with our command, it is rejected” (agreed upon). From this you may also discern the ruling on inserting the word sayyiduna (“our master”) into these prayers for the Prophet—a practice common among many Shafiʿis and others. The scholars have differed over it, as will be discussed in the forthcoming points.