Everything is God. Or Self. Or consciousness. Regardless of what you call it, it is all one thing, one unity. Buddha is simply one example of an individual who went beyond his individuality. In other words, he among others realized that the individual sense of self is a temporary and ultimately illusory thing and that it was only necessary up to a certain point. The big picture is that he was one with the whole, inseparable; still is in fact. Knowing this made him free and he lived as a God, and this inspired many to view him as such, and still does to this day.