“…authentic, provided that Thābit ibn ʿUbayd actually heard it from Zayd ibn Thābit.”

I say: I do not know what made al-Ḥākim unsure about Thābit’s hearing it from Zayd, when Thābit was his own freedman and has never been accused of concealment in transmission (tadlīs). Ibn Ḥibbān states in al-Thiqāt (1/6): “Thābit ibn ʿUbayd al-Anṣārī, a Kufan who narrates from ʿUmar and Zayd ibn Thābit; Ibn Sīrīn and al-Aʿmash relate from him, and he is the freedman of Zayd ibn Thābit.”

Some have claimed that Thābit ibn ʿUbayd al-Anṣārī is a different person from Thābit ibn ʿUbayd, Zayd’s freedman. Abū Ḥātim distinguished between the two in al-Jarḥ wa-l-Taʿdīl (1/1/454), and al-Ḥāfiẓ attributed this distinction to Ibn Ḥibbān in al-Tahdhīb as well. This is a mistake, however, for what I have just quoted from Ibn Ḥibbān shows he made no such distinction, and this is the position al-Ḥāfiẓ himself adopted in al-Taqrīb. In either case, both narrators are trustworthy (thiqa), and the chain is sound.

Al-Bukhārī cited the ḥadith in suspended form in his Ṣaḥīḥ, saying: “Khārija ibn Zayd ibn Thābit reported from Zayd ibn Thābit that the Prophet ﷺ ordered him to learn the script of the Jews.” Al-Ḥāfiẓ Ibn Ḥajar comments (13/161): “He supplied it in full with an unbroken chain in his book al-Tārīkh.” He then mentioned the other route that al-Tirmidhī suspended and added: “I obtained this chain with a lofty isnād in the work Fawāʾid Hilāl al-Ḥaffār.”

Aḥmad and Isḥāq recorded it in their Musnads, as did Abū Bakr ibn Abī Dāwūd in Kitāb al-Maṣāḥif and Abū Yaʿlā. The wording in the last reads: “I write to a people and fear that they may add to or omit from what I have written, so learn Syriac,” and he mentioned the report. Another route was transmitted by Ibn Saʿd. All of this rebuts the claim that ʿAbd al-Raḥmān ibn Abī al-Zinād was alone in narrating it, though it is true that none reports it from his father, from Khārija, except ʿAbd al-Raḥmān.