Chain: Yazīd ibn Hārūn → Muslim ibn ʿUbayd, Abū Nuṣayrah → Abū ʿAsīb, freedman of the Messenger of Allah ﷺ (may Allah be pleased with him). Rijāl: (1) Yazīd ibn Hārūn: Yazīd ibn Hārūn ibn Zādhān al-Wāsiṭī (d. 206 AH); thiqah mutqin. (2) Muslim ibn ʿUbayd Abū Nuṣayrah al-Baṣrī: graded maqbūl. (3) Abū ʿAsīb: a Companion who served as a freedman in the Prophet's ﷺ household. Takhrīj: the theme of Madīnah's protection from plague, and the plague as martyrdom for the believer, is soundly and extensively established in al-Bukhārī (5734) and (1880), and Muslim (2218), from ʿĀʾishah and Usāmah ibn Zayd, including the well-known statement that neither al-Dajjāl nor the plague would enter Madīnah. Commentary: This report frames epidemic disease within a providential and moral lens distinctive to Islamic theology: the plague, while a genuine calamity, is reckoned as martyrdom and mercy for the believer who dies of it while remaining in his place (as later ḥadīth clarify, neither fleeing from it nor entering the afflicted land), while representing a chastisement specifically for the disbeliever, a framing that shaped centuries of Muslim response to epidemics, including the juristic principle of neither entering nor fleeing a plague-stricken land.