The significance of the controversy surrounding divine justice in the development of Islamic theology cannot be overestimated. It split the community of theologians into two rival camps, with the Muʿtazilis being the most outspoken representatives of the first and the Ashʿaris of the second. The paramount theological importance of the split is manifest in the fact that the groups of the first camp, including the Imamis and the Zaydis, although also agreeing with each other on other theological matters pertaining to divine essence and attributes, often styled themselves collectively as the ‘upholders of justice’ (ahl al-ʿadl, al-ʿadliyya), not without a hint of pride. The importance of the issue may also be gauged by the relatively abundant space that discussion of this precept occupies in their theological works; the claim that the study of all five precepts of Muʿtazili doctrine may be called ‘the sciences of justice’ (ʿulūm al-ʿadl); and the tendency to reduce these precepts to only unicity and justice, with the first including the discussion on divine attributes and the remaining precepts going under justice.

Both camps agreed that God is just, but they diverged over the definition of justice, which led to a debate over the definition of the morality of acts and their consequences. Thus, at the core of the discussion lie the respective moral theories adopted by the two camps. The first camp, that containing the Muʿtazilis, believed in rationally comprehensible moral values, postulating the existence of objectively good and vile acts whose nature is independent of their agent and which necessitate clearly defined consequences. The other camp defended the thesis that acts are good or vile only as a consequence of divine command; they are morally neutral in themselves. But despite the fact that this sharp polarisation was centred on the disputed status of objectivist morality, it is also important to note that vehement disputes were taking place within each of these main camps. This fact is attested by the relatively meagre attention that the Basran Muʿtazilis gave to traditionalists and Ashʿaris compared to the elaborateness of their arguments against the views of Baghdadi Muʿtazilis.