—naturally—applies to one who had long hair, as was customary among the Arabs in earlier times and remains so in some lands today. He therefore forbade this and instructed that it be left loose, so that one’s prostration would be more complete, as may be understood from al-Nihayah and other works. See The Prophet’s Prayer Described (p. 151, 5th edition).

2387 — “Whenever he sneezed, he would praise Allah. He would then be told, ‘May Allah have mercy on you,’ and would reply, ‘May Allah guide you and set your affairs aright.’”

Ahmad (1/204) narrated it from Ibn Lahi‘ah, from Abu al-Aswad, who said: I heard ‘Ubayd ibn Umm Kilab narrate from ‘Abd Allah ibn Ja‘far, the Possessor of the Two Wings, as a report attributed to the Prophet, peace and blessings be upon him. I say: This chain of transmission is weak. The identity of ‘Ubayd ibn Umm Kilab is unknown, as stated in Tājīl al-Manfa‘ah. Ibn Lahi‘ah also had poor retention.

Al-Haythami said (8/56): “Ahmad and al-Tabarani narrated it. It includes Ibn Lahi‘ah, who is acceptable in hadith despite some weakness in him, while the rest of its narrators are trustworthy.” That is what he said. However, the hadith is authentically established as part of the Prophet’s instruction to his community, through the hadith of Abu Hurayrah and others; see al-Irwa’ (772).

I then found a corroborating report for it, narrated by Isra’il from Asbat ibn ‘Azrah, from Ja‘far ibn Abi Wahshiyyah, from Mujahid, from Ibn ‘Umar, who said: “We were sitting with the Prophet, peace and blessings be upon him, when he sneezed and praised Allah. They said, ‘May Allah have mercy on you.’ The Messenger of Allah, peace and blessings be upon him, replied, ‘May Allah guide you and set your affairs aright.’”