Muslim (8/94) and Aḥmad (2/308) narrated it through Yazīd ibn al-Aṣamm, from Abū Hurayrah, attributed to the Prophet. It also has two other chains from Abū Hurayrah, as well as many corroborating reports. See: “If You Were Not to Err” (no. 969), no. 970, and others. These include the hadith that follows, as well as hadith no. 1963, which comes several hadiths later. There I made a brief remark concerning what is intended by these hadiths.

1951 — “By Him in whose hand is my soul—or he said: By Him in whose hand is Muhammad’s soul—if you were to sin until your sins filled all that lies between heaven and earth, then seek Allah’s forgiveness, He would forgive you. And by Him in whose hand is Muhammad’s soul—or he said: By Him in whose hand is my soul—if you did not sin, Allah, exalted is He, would bring a people who would sin and then seek Allah’s forgiveness, and He would forgive them.”

Aḥmad (3/238) narrated it: Surayj ibn al-Nuʿmān related to us; Abū ʿUbaydah—that is, ʿAbd al-Muʾmin ibn ʿUbayd Allāh al-Sadūsī—related to us; Akhsham al-Sadūsī related to me, saying: I entered upon Anas ibn Mālik, who said: I heard the Messenger of Allah, peace and blessings be upon him, say—and he cited it.

Al-Haythamī said (10/215): “Aḥmad and Abū Yaʿlā narrated it, and its narrators are trustworthy.” This is correct, except with regard to this Akhsham, for no one declared him reliable other than Ibn Ḥibbān. It is stated in al-Ikmāl: “He is unknown.”

Al-Ḥāfiẓ said in al-Taʿjīl: “Neither al-Bukhārī nor Ibn Abī Ḥātim mentioned any criticism of him, and in his narration he explicitly stated that he heard directly from Anas. The hadith concerning seeking forgiveness that Aḥmad narrated from him has a corroborating report from Abū Hurayrah in Muslim.”

I say: He means the hadith immediately preceding this one, but it corroborates only its second part. As for the first part, it has another chain from Anas with similar wording, as follows: