A Medinan sura whose title is taken from verse 104. The sura opens by giving notice of the severance of the treaty with the idolaters because they had broken it, but the bulk of the sura deals with preparations and recruitment for the expedition to Tabuk, which took place in the heat of the summer of AH 9 (631 CE). The hypocrites and those who stayed behind and failed to support the Prophet are all censured. This is the only sura not to begin with the formula ‘In the name of God, the Lord of Mercy, the Giver of Mercy’; there is an opinion that suras 8 and 9 are in fact just one sura.
Source: The Qur’an (Oxford World’s Classics) by M. A. S. Abdel Haleem (Amazon Kindle Edition)