Imam Ahmad recorded it (1/450): Yaḥyā ibn Zakariyyā related to us, from his father, from Abū Isḥāq, from Abū al-Aḥwaṣ, from ʿAbd Allāh, from the Prophet, peace and blessings be upon him, to that effect.
I say: This chain of transmission is authentic, for all its narrators are trustworthy men included among Muslim’s narrators, were it not that Zakariyyā—namely, Ibn Abī Zā’idah—heard from Abū Isḥāq—namely, ʿAmr ibn ʿAbd Allāh al-Subayʿī—after the latter’s memory had deteriorated. However, Sufyān corroborated him in narrating it from Abū Isḥāq, except that he said: “...cannot impersonate me.” Ahmad recorded it (1/375, 400, and 440), as did al-Tirmidhī (2277), Ibn Mājah (3946), and al-Dārimī (2/123–124). Al-Tirmidhī said: “A good, authentic hadith.”
I say: Sufyān here is al-Thawrī, and he heard from Abū Isḥāq before the latter’s memory had deteriorated. Thus, the hadith is authentic according to Muslim’s criteria. Al-Ṭabarānī also narrated it in al-Awsaṭ (1/67/2, no. 1244) through al-Ḥajjāj ibn Arṭāh, from Abū Isḥāq, to that effect.
It also has a corroborating report from the hadith of ʿAbd Allāh ibn ʿAbbās, related as a saying of the Prophet, peace and blessings be upon him, with the wording: “Whoever sees me in a dream has indeed seen me, for Satan cannot impersonate me.” In another wording: “cannot impersonate me.” Ahmad recorded it (1/279) through Jābir, from ʿAmmār, from Saʿīd ibn Jubayr, from him. Its narrators are trustworthy men included among Muslim’s narrators, except for Jābir—al-Juʿfī—who is weak. But it has come through another route, narrated by ʿAwf ibn Abī Jamīlah, from Nadhīr al-Fārisī—who used to write copies of the Quran—who said: