كُلٌّ مِنْ ذٰلِكَ يَدُلُّ عَلَى مَعْنًى زَائِدٍ عَلَى مَفْهُومِ الْوَاجِبِ
Each predicate conveys meaning beyond the concept of the Necessary Existent.
Necessary existence tells us that a being does not depend on another for its existence. Knowing and powerful convey knowledge and power. One may understand what necessary existence means and still ask for a justification that its bearer has these particular perfections.
The phrase 'additional in meaning' does not mean an extra body, separable part, or independently existent deity. Conceptual distinction is not the same as physical composition or plurality of divine essences.