What do people when they say they believe in God? Are they making an intellectual statement, asserting the correctness of a certain body of Scripture? Are they describing a personal relationship with a spiritual being? Are they making a teleological claim about the meaningfulness of existence? Are they just reciting the beliefs of their parents? Modern society is decidedly secular; in many quarters admitting to belief in God is a serious faux pas, an admission of ignorance and superstition.
At the same time, the foundations of Enlightenment agnosticism and atheism are beginning to show signs of wear and stress. Advances in philosophy and physics in particular have led many to a sort of nihilistic skepticism, not only about God but about all knowledge. While the debate between theists and atheists is generally cast as a polarized battle between two diametrically opposed metaphysical, cultural, and ethical systems, even a cursory glance at the writings from both sides reveals that the terms and ideas used are often muddily vague. How much of the debate is really confusion and miscommunication? Can we really even argue about an idea as abstract and ineffable as God in the first place? What does the word "God" even mean?
At the center of this debate is the separation of a word or concept from what it describes. The word "chair" is not itself a chair. My name is not the same thing as my actual body and my history as a person. So the focus of our attempts to talk about and understand God is an issue of semantics: what do these words mean? And what, perhaps more importantly, do these words not mean? If our debates and discussions about God are going to be fruitful, we have to be clear with our semantics.
Getting back to the "chair" example, if someone asked me to define a chair, I think the most accurate and succinct definition would be "a human-made object with a horizontal surface designed for a single person to sit on and a vertical surface to support the person's back, and that is movable." Other similar objects, like stools and booths, would be excluded--stools have no back, and booths seat more than one person and are normally bolted to the floor or wall.
When we talk about God, though, are we talking about an object like a chair that can be perceived with the senses and then described? I'm not going to give my own answer(s) here, in part because I don't know that I have any good answers to give. But there's no question that considering these questions must be central to any person of faith. Is God a being we can perceive like other beings? Or is God Being itself, the very essence of all existence? Is God a prime mover, a first cause alone? Or is God cause and constant sustainer--transcendent and yet immanent? Can we communicate with God like a sort of super-human? Or does communing with God take radically different forms than we are used to as humans?
Ultimately, what do we mean when we talk about God? I don't think any of us will have any immediate answers. One might say that the practice of a religion is, at least ideally, itself the answer.