The close relationship between Arabic grammar and Islamic jurisprudence is a well-established fact. Less known is the relationship between Arabic grammar and Islamic theology, which comes as no surprise as theologians were usually interested in more general questions such as the nature of language or divine speech whereas the scope of most grammarians was limited to the analysis of given linguistic phenomena. On the other hand, all issues of grammatical analysis could potentially be of theological relevance. An interesting example thereof is the construction of the type mā ʾaʿẓama llāha ‘How mighty is God!’ It will be shown that al-Ḫalīl's (d. 160/776) analysis of this construction developed into a serious theological problem for his Basran successors. Furthermore, it will be discussed how other grammarians of Basran orientation felt uneasy with it for different theological reasons, whereas it raised no theological problem for grammarians who took a different approach. The fatwā by the jurisprudent Taqīyaddīn as-Subkī (d. 756/1355) about the permissibility of such expressions as well as their relationship to the names of God will also be examined.