Obeying The Messenger
This is too circular for me to garb onto, I am lost inside this circle Belief in God is the basic premise of religion, rest of the beliefs stem from this basic belief and are a necessary corollary of this belief. Without Prophet (and by extension without Quran), you would never be able to materialize the relationship between creator and the created in its truest form and with all its necessary details. In their absence, you will be able to reach this conclusion that there is a creator, but you will never be able to see through beyond that point.