Before the Baal Shem Tov, people thought of God as the One who directs all things from above and beyond.
The Baal Shem Tov taught that the life force of every thing—the source of its personality, its sense of pain and pleasure, its growth and life—is God. This is not to say that this is the entirety of God. It is only a tiny ray of God, for He is utterly beyond description. But all life force is God as He resides within every creature He made.