Al-Anam ('The Cattle'), 165 Meccan verses said to have been revealed in a single night, is a sustained argument for pure monotheism against the idolatry and superstitions of the Meccans, including their taboos about certain livestock. Its centerpiece is Abraham reasoning from the setting star, moon and sun to the one Creator who does not set (6:75-79).
The tradition that Al-Anam was revealed in a single night, transmitted through several chains and noted by al-Tabari, distinguishes it from most long surahs, which were typically revealed in stages across months or years responding to events as they arose; commentators read this unity of revelation as matching the surah's own tightly argued, unbroken case for monotheism. Abraham's reasoning from the star, moon and sun (6:75-79) is treated in classical exegesis as a model of argument from observation rather than only from prior scripture, since Abraham reaches monotheism through reflection on creation before any revealed law is given to him, a passage later cited in Islamic theology's arguments for natural knowledge of God. The surah's closing verses list a set of moral commands, kindness to parents, honouring agreements, avoiding indecency, that al-Razi's commentary calls a summary of the whole ethical law, comparable in miniature to the fuller legislation of the Medinan surahs.