Saint Thérèse of Lisieux (1873-1897), also known as “the Little Flower of Jesus,” was a French Carmelite nun who had wisdom beyond her years.  I stumbled across her reflections on living in the present in a little devotional I’ve been using lately, A Guide to Prayer for All God’s People:

If I did not simply live from one moment to the next, it would be impossible for me to keep my patience.  I can see only the present, I forget the past and I take good care not to think about the future.  We get discouraged and feel despair because we brood about the past and the future.  It is such folly to pass one’s time fretting, instead of resting quietly on the heart of Jesus.