Spinoza appears as a philosopher who has been discussed due to his thoughts in the history of philosophy, which is not fully understood, and therefore has not found a place in the history of philosophy. But Spinoza's thoughts gain importance with recent studies, which has done by contemporary researchers. Therefore, to understand and enlighten Spinoza's views, via his works, it is necessary to explain his discussions and his opinions in a holistic approach. If we resemble the history of philosophy as a river, Spinoza, who is born and grown in this river of knowledge, expressing his own ideas in that river and enriching the river with his thoughts, was influenced by the previous philosophers and also, he affects next philosophers. As a matter of fact, Spinoza's Ethics, where Spinoza expresses his own ideas clearly and writes them with his own method, undoubtedly has an important place in understanding the continuity of the history of philosophy. Ethics, which was written as "Demonstrated in Geometrical Order and Divided into Five Parts", gives the reader various clues about his thought method. We will examine in this article the concepts of substance, God, attribute, attitude and modus in the philosophy of Spinoza based on Spinoza's Ethics. Then, we will study Spinoza's accounts on God in terms of the philosophy of religion.