In the miracle of the wedding feast at Cana, Jesus changes the water into wine. There are two levels of symbol working here. On the religious level, the water changed into wine signifies the Old Covenant with Israel being elevated and brought to perfection in Christ's New Covenant with the Church. But this is true on the natural level as well. St. Thomas Aquinas taught that grace presupposes nature and elevates it. If we invite Christ into every aspect of our lives -- our work, our leisure, our relationships -- He will elevate and perfect the naturally good so that the natural good now becomes a vehicle for the supernatural.