The River of Life from the Temple of God

The Lord next shows Ezekiel water flowing out of the temple. It starts as a trickle, then gets deeper and deeper and is eventually impossible to cross. What does it represent? Clearly, life. But is it purely spiritual? Is it purely physical/literal? Or is it both? As with this river, God takes something small in our lives and provides the power and volume to make it profoundly effective -- so He can get the glory!