According to Ibn Rushd: “The cause of their differences lies between the literal and the intended meaning. The literal meaning determines the classifications, but the intended meaning shows that priority should be given to the needy according to the immediacy of their needs since the aim [of the institution of zakah] is to eliminate poverty. The enumeration [of the categories] in the Qur’an is meant to distinguish the different kinds–that is, the people eligible for zakah, and not necessarily their grouping. The first interpretation is the literal one while the second is the intended interpretation.” Ash-Shaf’i builds his case on the hadith of as-Suda’i which is related by Abu Dawud. A man came to the Prophet, upon whom be peace, and asked for zakah. The Messenger of Allah, upon whom be peace, said: “Allah has not left the matter to the judgment of a prophet nor to others. He has laid the rules for it–that is, He has classified [the beneficiaries] into eight categories. If you fit into any of these, I will give you your due.”
Section : Why the Scholars Differ.