This type [of hadith] they have unanimously agreed upon as admissible as evidence, and that if it comes through multiple chains, or if there is something in the chapter that bears witness to it, it rises to the rank of ṣaḥīḥ li-ghayrihī (sound due to others). Indeed, more than one of the hadith scholars who committed themselves to authenticity in their compilations have included it, while stating that it is below the ṣaḥīḥ (sound) level—such as Imam al-Bukhārī and Imam Muslim, for they, may Allah have mercy on them, did not commit themselves in the hadiths of their two books to all of them being at the highest degrees of authenticity. Likewise, the two Imams Ibn Khuzaymah and Ibn Ḥibbān. This type of ḥasan (fair) hadith—which is ḥasan li-dhātihī (fair in itself)—is present in al-Jāmiʿ [of al-Tirmidhī], but he, may Allah have mercy on him, distinguishes it by saying: "ḥasan gharīb" (fair and singular) or something similar. An example of it is the hadith of Isrāʾīl (1), son of Yūnus, son of Abī Isḥāq al-Sabīʿī, from Yūsuf, son of Abī Burdah, son of Abī Mūsā al-Ashʿarī, from his father, from ʿĀʾishah, who said: "When the Messenger of Allah, peace and blessings be upon him, came out from the privy, he would say: 'Ghufrānaka' (Your forgiveness)." Al-Tirmidhī said: "Ḥasan gharīb; we do not know it except from the hadith of Isrāʾīl, from Yūsuf, son of Abī Burdah, and this is not known except in the hadith of ʿĀʾishah."

As for al-ḥasan li-ghayrihī (fair due to others), its origin is ḍaʿīf (weak), such as when its chain contains an obscure narrator, or one with poor memory, or one described as having become confused (ikhtilāṭ), or as a mudallis (one who conceals), or one whose disparagement and praise are disputed in a way that makes weighing [the evidence] difficult. Rather, fairness comes upon it only through the supporting witness (al-ʿāḍid) that supports it, so it becomes acceptable due to the existence of the supporting witness. Were it not for the supporting witness, the quality of weakness would have continued to apply to it.

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(1) The hadith (no. 7).