[Biographical Notes in 'Reliance of the Traveller', Noah (Nuh) Ha Mim Keller, USA: Sunna Books, 1991 CE, x283 (pg. 1085) ]

Nasa'i (Introduction) is Ahmad ibn `Ali ibn Shu`ayb ibn `Ali ibn Sinan ibn Bahr ibn Dinar, Abu `Abd al-Rahman al-Nasa'i, originally of Nasa, Persia, born in 215/830. He was a Shafi`i scholar and judge, a hadith master (hafiz) and Imam. Educated in hadith by scholars like Ishaq ibn Rahawayh, Abu al-Qasim Tabarani, and others during travels to Khurasan, Iraq, Syria, the Hijaz, and the Arabian Peninsula, he eventually settled in Egypt.

 It is related that he used to fast every other day, and was fond of women, having four wives whom he took turns with as well as a number of concubines. While he authored works on the merits of the Companions and an outstanding volume on the excellences of Imam `Ali ibn Abi Talib (Allah be well pleased with him), his main work is his Sunan [Sunnas], one of the six great hadith collections of Islam. Daraqutni said of him, "Abu `Abd al-Rahman leads all others of his time who are mentioned in the field of hadith," and when Dhahabi was asked who was more learned, Nasa'i or Muslim, he replied that the former was, a verdict that Imam Taqi al-Din Subki concurred with. After a lifetime of worship and of devotion to Sacred Knowledge, Nasa'i was martyred in 303/915 in Damascus for his love of Imam `Ali by remnants of the Kharijite sect, who gave him a beating from which he died (ibid., 1.171; and Tabaqat al-Shafi`iyya al-kubra (y128) 3.14-l6).