It's a tragedy of Western culture that relegates the heart to a mere metaphor of human emotion. It's the only culture that does that; every other civilization seems to have understood that the heart is quite literally the seat of a higher level of understanding. Recently scientists have discovered that the heart has a sensory field more powerful than the brain, connected to a parallel neuron network of its own. It's not simply a figure of speech when the Bible refers to the heart as the one place where you can hear the voice of God. He doesn't speak to the intellect, so if you don't have your heart attuned to His voice, you can't hear Him at all.