The question of God's existence is a perplexing one, the only evidence we have of God is what we are told from those who worship him, and unknowns can be debated logically if a higher being is in control.
It has been written that in the beginning there was man and there was woman, and God put the two together to create a new race of beings. We are to assume then that God gave these beings a soul to distinguish them from other beings, for example, plants. The soul is often argued to be a mystical form that is immortal and can not be proven to be anything else.
Assuming this argument to be valid then God is a supreme being to have created humans. We have several high beings that appear to stem from this one divine being, for example, Buddha. Therefore it makes sense those who were pure in religion were considered divine beings by their pupils.
We can not discern that there was not a God in the beginning, because if he was alone in this endeavor of creating our world then there are no witnesses. It is then reasonable to speculate God spread the word to his disciples, who in turn set about proving that he did exist, based on what the Bible told them. In Aquinas's Argument from Efficient Causation each thing is caused to exist and there can be no regression of causes of existence. So there must be a first cause of existence, God. It is in this simple logic such as this that the people of the time based their philosophy on. Aquinas argument is not valid for nothing is its own cause, everything is circular in time. In his argument he leaves the possibility that God may not exist any more. He came, he created, and he left.
It is reasonable to say there is no way to check the existence of God using our senses. God could be a non-physical being that we can not see or feel. Then if that is to be valid, how can we prove it?
There are instances in life that simply can not be explained. Let's say death for example. Death is another of life's mystery,