Throughout the history of mankind, the Prophets were sent to convey the same message: Monotheism, namely that there is only one God. The teaching of monotheism is a fundamental basis of divine religions because it is delivered based on revelation.
In Islamic teachings, the principle of monotheism is called tauhid, which is to unite God, that God is only one, there is no partner for Him, there is no essence like Him, only He is worshiped, and only Him is the place to ask. This principle should be reflected in social life.