as al-Hafiz himself stated in al-Taqrib, and no one has declared him reliable. So how could al-Hafiz deem his chain of transmission good?! There is no explanation for this except the predominance of human fallibility, or that some textual corruption may have occurred in his name in the printed edition of al-Muʿjam—which I consider unlikely. And Allah knows best.
Then I found what I had considered unlikely: I saw the hadith in al-Tabarani’s al-Muʿjam al-Awsat, through the route mentioned in al-Muʿjam al-Kabir. There, at 6/96/5201, the chain explicitly identifies him as “ʿAbd al-Malik ibn Husayn, Abu Malik al-Nakhaʿi.” Al-Tabarani said:
“No one narrated it from ʿAbd al-Malik ibn ʿUmayr except ʿAbd al-Malik ibn Husayn.”
Then al-Hafiz said—and he did well:
“Qadi Husayn, in his Taʿliq, attributed it to a report of Aishah, but I have not found it among her hadiths. I say: Its meaning is found in Muslim’s narration from her: ‘When he bowed, he neither raised his head nor lowered it, but kept it between the two.’ The meaning of this has already preceded in the hadith of Abu Humayd.”
I say: He is referring to the hadith recorded by al-Bukhari (no. 828) on his authority: He was sitting with a group of the Companions of the Prophet, and Abu Humayd said:
“I know the prayer of the Messenger of Allah better than any of you. I saw him: when he bowed, he would place his hands firmly on his knees, then bend his back.”
The hadith has been traced to its sources in al-Irwaʾ (2/13–14) and Sahih Abi Dawud (722).
Al-Hafiz explained the word “bend” in al-Fath (2/308), saying:
“That is, he bent it while keeping it level, without arching it; al-Khattabi mentioned this.”
This is equivalent in meaning to the hadith under discussion for whoever reflects upon it, and al-Hafiz alluded to this shortly before.