Everyone has their own beliefs. To believe in something you have to have thoughts about it. To have thoughts about it you have to have a mental process of some sort, ie: you need a brain. Hawking has a brain, a tree, to the best of our knowledge, doesn't.
When I first read the article I immediately thought about origin. Origin, to me, is the sticking point of every discussion about the existence of a god, as we define it. Hawking says gravity is why he chose physics over God. What is the origin of gravity? How did it begin?
Back in my Catholic grade school the nuns taught "God was, is and always will be." Therefore God has no origin. My mini scientific mind imagined traveling back through time and finding God there. Then I went further back and there was God. Even back when there was nothing, there was God. And on and on my mind travel went back until I tired of the exercise.
With Hawking's theory we have to assume the same thing for gravity. No matter how far you go back in time, there is gravity. Does gravity then become God? If gravity is the creator of our universe and has no origin, doesn't that make gravity God-like?
When my time on this earth comes to a close, I will have the answer. Or maybe the lights will simply go out. Until then, this is simply a mental exercise.