Aristotle considers metaphysics a science that discusses Being qua Being (or "Being insofar as it is Being") and its essential attributes. Alongside "Being qua Being," he also speaks of absolute Being. The multiple meanings of "Being" in Aristotle's thought have led interpreters to diverse understandings of what Aristotle truly meant by "Being qua Being? "They would have disagreements. A disagreement that starts from ontology and impacts their theology. Among Muslim philosophers, Avicenna and Averroes (Ibn Rushd), and among Christian philosophers, Albert the Great(Albertus Magnus) and his student Thomas Aquinas, have commented on this matter. In Avicenna's view, what is meant by 'Being qua Being' is a universal concept that applies to all Beings, including the Necessary Existent per se. Consequently, the Necessary Existent is part of the subject matter of philosophy. However, Averroes introduced the highest substance to explain "Being qua Being" and considered God the subject of philosophy. Consequently, he regarded the proof of God as part of the problems of natural science. In Albert the Great's view, "Being qua Being" is the simple existence as the first creation of God, and this simple existence is the subject of philosophy. In Thomas Aquinas's perspective, "Being qua Being," although the subject of philosophy, applies only to contingent Beings, and God is the cause of this "Being qua Being." A comparative study of these disagreements and the reasons behind them forms the framework of this article.