A heart that is full sees the good. Thankfulness is the highest expression of faith, because it believes it has received. Natural man tends to focus on what's negative, but a thankful heart transforms the natural to the spiritual, and reminds a person of the true, bigger perspective of all that is good, especially God. True riches are spiritual because they don't run out or get diminished or old. They flow from an inner fountain of Life and make us givers of true riches to those around us.