In this chapter, Maimonides emphatically states that strict monotheism requires the denial of essential attributes (al-sifaat al-zaatiya الصفات الذاتية) predicated to God.

to truly hold the conviction that God is One and possesses true unity, without admitting plurality or divisibility in any sense whatever, you must understand that God has no essential attribute in any form or in any sense whatever, and rejection of corporeality implies the rejection of essential attributes Those who believe that God is One, and that He has many attributes, declare the unity with their lips, and assume plurality in their thoughts.

Of the latter kind, he gives the analogy of Christians — explicitly — who say that God is both One and Three at the same time, and of Muslims — implicitly — who say that God is one but then assign to him multiple attributes (the 99 names of God). About both of these theological points of view, Maimonides is respectfully disdainful: “… as if our object were to seek forms of expression, not subjects of belief”.

In the process of making these points, Maimonides explains what he means by the term “belief” (al-i’tiqad الاعتقاد), but I won’t go into that for now.