Al-Kawthar ('Abundance'), 3 verses, is the shortest surah in the Quran. It grants the Prophet 'al-Kawthar' (understood as a river or fount in paradise, or abundant good), commands prayer and sacrifice to God, and answers a detractor that it is he, the hater, who is 'cut off' (108:3). Classical commentary connects this shortest surah in the Quran directly to a specific mockery: al-As ibn Wa'il, a Meccan chief, is reported to have called the Prophet abtar, cut off, after the deaths of his infant sons, meaning a man without a male heir to carry his name forward, a serious insult by the standards of the surrounding tribal culture. Al-Kawthar, generally understood as either a river or an abundant fount in paradise, or more broadly as overflowing good in this world and the next, answers that mockery directly, promising the Prophet a legacy the insult had denied him, and it is his opponent, the surah insists, who is truly 'cut off' (108:3).
Classical commentators read al-Kawthar itself in more than one register: some identify it narrowly with a specific river or pool the Prophet will possess in paradise, from which his community will drink on the Day of Judgement, a reading elaborated at length in later hadith literature describing the pool's dimensions and taste, while others read it more broadly as abundant good of every kind granted in this world and the next, prophethood, the Quran, and numerous spiritual descendants among them, the two readings generally treated as complementary rather than competing in classical exegesis. The surah's instruction to 'pray to your Lord and sacrifice' (108:2) is connected by some commentators to the annual sacrifice performed at Eid al-Adha, though the verse itself specifies no particular occasion.