If a divine creator of the Universe does exist and directly intercedes in people’s lives, then there must be clear evidence that can be verified by anyone. Otherwise, we must simply take other people’s word for it, meaning that we must have faith in their veracity.
The bulk of human experience strongly argues for a Universe that operates on a set of physical laws that can be mathematically described and applied predictably to a set of physical entities. We do not fully grasp these laws or have a complete picture of the entities they operate on, nor are we ever likely to. Like a computer attempting to do calculations to 10 digits of resolution and only having enough memory and processing power to handle four digits, we can only crudely approximate how the Universe operates (the results of the calculation). The approximate picture we have does not include a creator, nor is it required to explain what we see. If the presence of a divine creator is part of the Universe we can never comprehend, our innate limitations render this fact superfluous.
Personal experience is another way to test the existence of a creator, and even there the evidence is at best equivocal. Through biological or psychological (rather than supernatural) means, we can stimulate the same experiences of divine presence that the faithful report.
Reports of extraordinary events (what some have called miracles) are easily explainable by the laws of probability, if not outright exaggeration. Just because something is extremely improbable doesn’t mean it won’t happen; a classic example is physicist Richard Feynman’s observation that we observe very improbable combinations of letters and numbers on license plates every day. There is an entire cottage industry devoted to showing how human intuition is very poor at dealing with probability.
Given all of these considerations, I (and others far more knowledgeable than me) have concluded that the concept of a divine creator is a human artifact. The part of reality it is useful in explaining does not have to do with the origins or properties of the Universe, but rather the psychology and biology of humans, as well as the history that derives from the related perceptions of people.