Regarding Cyril’s theological writings, Campenhausen says: “He initiated the practice of deciding questions of belief not solely on the basis of the Bible but with the aid of appropriate quotations and collections of quotations from acknowledged authorities. ”
४१५ मध्ये हायपाशा नावाच्या एका नामवंत तत्त्वज्ञान्याची निर्घृण हत्या करण्यासाठीही त्याला जबाबदार ठरवले जाते.