It is natural for all humans to seek a father figure - someone to look up to - someone to set boundaries - someone to protect us - someone to give us certainty in an uncertain world. As children, we had our flesh-and-blood parents to fill those roles, but at a certain age, we found to our shock that our parents were not infallible - they could not protect us from life's vagaries. Ah, we now suppose that an even more powerful father figure is "up there."
The captivating power of the god concept is that it defies all logic and rationality. Try to disprove Santa Clause. You can't, because the whole idea is so nonsensical. Perhaps you remember believing in Santa Clause? If you were "good," a smiling father figure would give you gifts, while if you were "bad," you would get a lump of coal in your stocking. Santa Clause sounds very much like the god concept, doesn't he?
People believe in a god because their fear of the unknown, both death itself and the uncertainties of life, requires the invention of a father figure to provide reassurance. While logic and rationality are meaningless concepts to true believers, let me briefly point out the overwhelming illogic of "god" as a source of creation. The crux of the argument is the question, "If god created us, who created god?" Human beings and the rest of nature are truly wondrous and magnificent, and it is virtually beyond imagination that we could have evolved spontaneously. However, it is infinitely further beyond imagination that a god could have evolved spontaneously. As a comparison, if I can't imagine a human being lifting 10,000 pounds, my response should be to imagine a super-human lifting 10 million pounds, right? Superman, Santa Clause, and god - all imaginary.
Having dispensed with the fiction of "god" as a being - an entity with personality - an arbiter of "good" and "evil," let's look at the formless living energy that runs through us and unifies all life. My word for this energy is Spirit. Spirit is our palpable connection with all living beings and all who have gone before. Spirit is not judge and jury on human behavior, but a common thread that runs through all life. If you wish to use the word God for this Spirit you will not be alone, but you will be among a small minority, as the term "God" is interpreted by most as referring to a superhuman father figure.
I highly recommend the book "How To Know God" by Deepak Chopra. The book describes the Seven Stages of Belief in God, beginning with Protector (vengeful, judgmental), and ending with God of Pure Being ("can only be experienced by going beyond experience"). Depak Chopra's Stage Seven God is the energy I know as Spirit - the energy that joins me in Unity with all of life.