John of Damascus devoted sixteen times the average chapter space to Islam

Evidence

Liber de haeresibus (John of Damascus, Liber de haeresibus, in P. Bonifatius Kotter, ed., Die Schriften des Johannes von Damaskos, 5 vols. [Berlin, 1969–81], 4:19–67). In other words, this one chapter comprises 16 percent of the text; it is sixteen times the size of the average chapter. One other chapter is as long, chap. 80, on the Massalianoi. — John V. Tolan, Saracens, 1515