Such a person lacks all knowledge and insight into the...
Such a person lacks all knowledge and insight into the nature of God's unique being and is blind and ignorant. "The one who is thus deprived of vision will attempt to point to God (i.e., restrict Him to a given time and place), and whoever does this posits imprisoning limits for the Creator of all being and makes Him finite. Whoever limits and restricts Him in this way regards Him as a measurable quantity.
Whoever asks: "Where is God?" unintentionally makes of Him a body enclosed within another body, and whoever asks, "In what is God engaged?" unintentionally states that certain places are empty of His being." So each attribute is infinite and coextensive with the infinitude of the essence. God is free of and exempt from finite attributes that might be distinct from each other and separate from the essence.
Once we realize that God's being derives from Himself, it follows that an absolute being is infinite in all respects. If being and non-being are equally conceivable for an entity, it must acquire being from some external cause to come into being; self-origination is, after all, impossible. It is, then, only absolute being that derives from itself; all other realities are subordinate to it and knowable only by means of it.
Once an essence is identical with its own existence, it is infinite with respect to knowledge, power, non-origination and everlastingness, for all of these are forms of being, and an essence that is identical with existence must necessarily possess all these perfections to an infinite degree. The oneness of God is one of His foremost attributes.
All the heavenly religions, in their original and undistorted teachings, have summoned mankind to a pure affirmation of God's unity, untainted by the ascription of partners to Him. Such ascription of partners, in all its forms and dimensions, is the most harmful error to which man is liable. It has occurred throughout history as a result of ignorance, unawareness, and turning away from the guidance of reason and the teaching of the Prophets.
If men believed in God according to correct thought, the proofs of reason and the guidance of the Prophets, it would be impossible for them to accept any contingent phenomenon or created thing in His place, and to imagine that any other being might be His partner or equal in commanding and controlling the destinies of the world, or even have some share in administering the order of the universe.