Abstract
What is presented in this article is the explanation and confirmation of three claims about the Knowledge of religion of Muslim philosophers: First. Muslim philosophers influenced by Plato and Aristotle have considered man as a social being. This means that man continues to live and survive in the form of presence in city, and the formation and survival of city requires law. But the law they introduce for the administration of city is not a human law, but a divine law, and that law is nothing but the divine religion. Therefore, according to Muslim philosophers, the nature of religion is the law. Second. Since Muslim philosophers have considered religion as a law, they have never questioned the existence of this law; That is, they have not asked what kind of existence religion as a law has in the outside world. Third. Although Muslim philosophers have expressed ontological points under the concept of religion as words and books and the like, they do not consider religion to be ontologically authentic. They have never had a coherent, codified and independent discussion about religion from the perspective of ontology. The basic question about religion, which has been neglected in Islamic thought and culture so far, is this: How does religion exist as an entity? The difference in approach regarding the existence of religion will cause a difference in the way of encountering religion and establishing a relationship with religion. Therefore, the ontology of religion is not just a theoretical discussion and it has many practical effects.
 
Extended Abstract
Introduction
The basic question about religion, which has been neglected in Islamic thought and culture so far, is this: How does religion exist as an entity? The difference in approach regarding the existence of religion will cause a difference in the way of encountering religion and establishing a relationship with religion. Therefore, the ontology of religion is not just a theoretical discussion and it has many practical effects.
What is presented in this article is the explanation and confirmation of three claims about the Knowledge of religion of Muslim philosophers:
First. Muslim philosophers influenced by Plato and Aristotle have considered that man continues to live and survive in the form of presence in city, and the formation and survival of city requires law. But the law they introduce for the administration of city is not a human law, but a divine law, and that law is nothing but the divine religion. Therefore, according to Muslim philosophers, the nature of religion is the law.
Second. Since Muslim philosophers have considered religion as a law, they have never questioned the existence of this law; That is, they have not asked what kind of existence religion as a law has in the outside world.
Third. Although Muslim philosophers have expressed ontological points under the concept of religion as words and books and the like, they do not consider religion to be ontologically authentic. Not only have they not discussed and questioned the existence of religion as a law, but they have never had a coherent, codified and independent discussion about religion from the perspective of ontology.
The basic question about religion, which has been neglected in Islamic thought and culture so far, is this: How does religion exist as an entity?
 The difference in approach regarding the existence of religion will cause a difference in the way of encountering religion and establishing a relationship with religion. Therefore, the ontology of religion is not just a theoretical discussion and it has many practical effects.
Method
In this article, three claims of Muslim philosophers such as Farabi, Ibn Sina, Suhravardi, Nasir al-Din Tusi, Mulla Sadra have been explained and analyzed in a documental way about Knowledge of religion.
Findings
In the following article, an attempt was made to explain and establish three claims:
First. Prominent Muslim philosophers mentioned religion as law in the context of Greek philosophy. In this regard, an attempt was made to explain the view of Greek philosophy - Plato and Aristotle - regarding the need for law, and also to show how the legal dress worn by prominent Islamic sages - from the time of Farabi to Mulla Sadra - was worn.
Second. Muslim philosophers were influenced by many factors, including the influence of Greek philosophers because they looked at religion as a law, it was not possible for them to look at religion from other perspectives, including ontology, so they did not ask such questions from the perspective of ontology: What are the characteristics of religion as a law?
Third. Also, they did not raise this question: What is the existence of religion, regardless of whether it wears the clothes of law or not?
Conclusions
From the point of view of Greek Plato and Aristotle, revealed religion was not relevant, and therefore they were not concerned with determining the relationship between religion and philosophy, nor were they concerned with determining the relationship between religion and politics. Therefore, for example, if Plato in the tenth book of the Laws discusses the relationship between some theological or religious topics, such as the role of law in making people believe in God and the like, or if in the fourth book of the Laws he discusses the rule of God and the like, hhis is not what he means at all relationship between religion and philosophy or determining the relationship between religion and government and politics
Muslim philosophers from Farabi to Allāma Tabātabāī, influenced by the Platonic-Aristotelian explanation of the role of law in society, have referred to the essence of Islam as "law": a law to govern human beings - whether in society or individually - and also to make people happy. It is worth mentioning that, in order to put the Greek law on the body of Islam, and in other words, to put the Islamic religion on the body of the Greek law, Muslim philosophers needed to clarify relationship between philosophy and religion, religion and politics, and philosophy and politics. Therefore, Muslim philosophers first explained their macro-narratives of the relationship this trinity - that is, philosophy, religion and politics - to each other and in the light of this relationship, they explained the nature of religion as a law.