and al-Dhahabī agreed with him. I said: There is a disagreement between Saʿīd ibn Salamah and Zuhayr ibn Muḥammad regarding the lineage of this Ṣāliḥ; the former said: "ibn Kaysān" and the latter "ibn Abī Ṣāliḥ." Both have weaknesses in their memory, but Saʿīd is in a better condition than him, and whether his narration is more reliable or Zuhayr's, each of the two Ṣāliḥs is trustworthy in ḥadīth, especially Ṣāliḥ ibn Kaysān, for he is used as evidence in "the two Ṣaḥīḥs." And what supports that it is him is that they mentioned him among the narrators from ʿAbd Allāh ibn Abī Umāmah, not the other, and Allāh knows best. Then I saw that the ḥadīth was recorded by al-Qaḍāʿī in "Musnad al-Shihāb" (6/2/1) through the route of Zuhayr, who said: from Ṣāliḥ ibn Kaysān, so I concluded with what I had preferred, and it became clear that what is in "al-Mustadrak" is an error from some of the narrators, if not from al-Ḥākim himself. Some narrators inserted a man between ʿAbd Allāh ibn Abī Umāmah and his father, as Muḥammad ibn Isḥāq said: from ʿAbd Allāh ibn Abī Umāmah from ʿAbd Allāh ibn Kaʿb ibn Mālik from Abū Umāmah who said: "The Companions of the Messenger of Allāh (ṣallá Allāhu ʿalayhi wa-sallam) mentioned the world one day in his presence, so the Messenger of Allāh (ṣallá Allāhu ʿalayhi wa-sallam) said: 'Do you not hear, do you not hear? Indeed, simplicity is part of faith, indeed, simplicity is part of faith,' meaning austerity." It was recorded by Abū Dāwūd (4161). I said: And Ibn Isḥāq is a known mudallis, and he narrated it with ʿanʿanah. He was followed up, as Ismāʿīl ibn ʿAyyāsh narrated it from ʿAbd al-ʿAzīz ibn ʿUbayd Allāh from ʿAbd Allāh ibn ʿUbayd Allāh ibn Ḥakīm ibn Ḥizām that Abū al-Munīb ibn Abī Umāmah (he is ʿAbd Allāh ibn Abī Umāmah) informed him that he met ʿAbd Allāh ibn Kaʿb ibn Mālik: Your father told me, so he mentioned it. It was recorded by al-Ṭabarānī. Then he and al-Ṭaḥāwī narrated in "Mushkil al-Āthār" (1/478 and 4/151) through the route of