33. Al-Ahzab

Al-Ahzab ('The Combined Forces'), 73 Medinan verses, is named for the confederate armies that besieged Medina in the Battle of the Trench. It regulates the households of the Prophet, introduces the ordinance of modest dress, ends the practice of adoptive-son marriage bars through the case of Zayd, and describes Muhammad as the 'Seal of the Prophets' (33:40).

The Battle of the Trench, fought in the fifth year after the emigration when a coalition of Meccan, Bedouin and Jewish tribal forces besieged Medina, is remembered in the biographical tradition for the defensive trench dug on the advice of the Persian companion Salman al-Farisi, a tactic unfamiliar to Arabian warfare that stalled the siege until the coalition's own internal divisions and a storm forced its withdrawal, an episode the surah reads as direct divine intervention 'that you did not see' (33:9). The case of Zayd ibn Haritha, the Prophet's adopted son whose marriage to Zaynab bint Jahsh ended in divorce before Zaynab's marriage to Muhammad himself, is addressed directly in the surah (33:37) and used to overturn the pre-Islamic Arabian custom of treating adopted sons as full sons for purposes of inheritance and marriage prohibition, a change the Quran states explicitly rather than leaving to later legal inference. The declaration of Muhammad as 'the Seal of the Prophets' (33:40) is the Quranic text most directly cited across Islamic theology for the doctrine of the finality of prophethood, understood across the mainstream tradition as closing the line of messengers sent to humanity.

Al-Ahzab supplies the scriptural basis for one of the most frequently spoken formulas in Islamic devotional life: 'indeed, God and His angels send blessings upon the Prophet; O you who believe, ask blessings upon him and greet him with peace' (33:56). Known as the practice of salawat, invoking blessings on Muhammad, the formula is recited after his name is mentioned in speech or writing, woven into the five daily prayers, and repeated independently as an act of devotion in its own right, with entire genres of devotional literature composed of collected salawat formulas for recitation.

Classical commentary discusses the verse's striking claim that God Himself, not only angels or believers, sends blessings on Muhammad, a formulation exegetes read carefully to avoid implying any deficiency in Muhammad that blessing remedies, generally understanding divine blessing here as honour and exaltation rather than correction. The instruction that believers do likewise is read as establishing salawat as a communal obligation of respect rather than an optional devotional flourish, which is why the phrase or its abbreviations appear so consistently attached to Muhammad's name across Islamic religious writing of every period.