The way many theists view God today is similar to the way that polytheists and idol worshipers viewed their own gods, except that God (with a capital G) is more powerful, longer in duration and alone. This does not mean that theism is incorrect, it only means that some people have an incorrect and erroneous understanding of God and proper theism.  

Atheists, taking up this erroneous understanding of God, argue that such a God, by virtue of being a contingent and limited being like Zeus, should be observable and subject to scientific scrutiny like any other object or being currently existing in the world. Since there is no observable evidence demonstrating the existence of such a being, it is not sensible to believe in his existence.  

Atheists conclude that they are not too different from monotheists except that they just go one god further in their rejection of supernatural gods. Muslims, especially those who follow the school of the Ahl al-Bayt (as), reject this interpretation of God. 

According to the Prophet Muhammad (ṣ) and the Imams of the Ahl al-Bayt (as), the Muslim God, or Allah, is the source and fountain of all of existence, He is what grounds “being” without which nothing, not even the thought of a mythological god, could exist, even for a split second. Since the Islamic God is not a contingent object or being, He cannot be observed like a planet can, but this does not mean that there is no evidence for His existence.  

The school of the Ahl al-Bayt (as) believes that evidence for God’s existence, that is, the God of Tawhīd, can be found in logic, the human intellect and the experience of the spiritual heart. This will be covered in more detail in the next series of lectures.