Diya? al-Din al-Makki (d. 559/1163-64) was a specialist of theology and law and the preacher (khatib) of the Shafi'i congregation in Rayy of his time. Diya? al-Din is, however, best known as the father of the famous theologian and critic of Avicenna (d. 428/1037), Fakhr al-Din Razi (d. 606/1210), often referred to as Ibn al-Khatib, certainly in his younger years. Diya? al-Din studied Ash?ari theology in Nishapur under Abu 'l-Qasim b. Salman al-Ansari (d. 512/1118), himself a student of Imam al-Haramayn al-Juwayni (d. 478/1085). Besides, he also studied in Marwarudh, hometown of the Shafi?i jurist al-Husayn b. Mas?ud al-Farra? al-Baghawi (d. 516/1122). The work of which the one remaining volume is published here is one of the largest works in early Ash?ari theology. It gives a fine impression of the discussions around some of the main differences between the Mu?tazila and the Ash?aris, besides its importance as a source of his son's ideas.