I say: Opinions about him differ. Al-Mizān states: “Ibn Maʿīn and others, as well as Muḥammad ibn Saʿd, al-Nasāʾī, and al-Dāraqutnī, declared him reliable. Abū Ḥātim said, ‘His ḥadith is sound; there is no harm in it.’ Al-Bukhārī remarked, ‘There is some reservation about him.’ Aḥmad said, ‘He reported a rejected (munkar) narration.’ Ibn Ḥibbān noted, ‘He used to err,’ and al-Jawzajānī judged him unreliable, counting this ḥadith among his objectionable reports.”

Ibn Ḥajar writes in al-Taqrīb: “Truthful, though he sometimes errs.”

I add: The remaining transmitters in Aḥmad’s chain are trustworthy—men cited by both al-Bukhārī and Muslim—so in my view the isnād is ḥasan. Ibn Ḥajar likewise says in Fatḥ al-Bārī: “It was narrated by Aḥmad and al-Nasāʾī, and their transmitters are reliable.”

Al-Nasāʾī records it through the route of Abū ʿAwānah, as noted in al-Bidāyah, and they add: “He used to enter the mosque while in a state of major ritual impurity (junub) because he had no other way in.”

Al-Dhahabī judged the report to be munkar, yet Abū Balj was not its sole narrator; rather, it has many corroborating reports. Among them is the narration from Saʿd ibn Abī Waqqāṣ who said: “The Messenger of Allah ﷺ ordered that all the doors opening into the mosque be closed, leaving only ʿAlī’s door.”