O Trinity of blessed light,O Unity of princely might,the fiery sun now goes his way;shed thou within our hearts thy ray.To thee our morning song of praise,to thee our evening prayer we raise;O grant us with thy saints on highto praise thee through eternity.St Ambrose of Milan (c. 340-397)  To the Trinity be praise! God is music, God is life that nurtures every creature in its kind. Our God is the song of the angel throng and the splendour of secret ways hid from all humankind,but God our life is the life of all.St Hildegard of Bingen  In Treasury of the Catholic Church, compiled by Teresa de Bertodano (Darton, Longman and Todd, 1999)Holy Spirit, spirit of truth, come into our hearts; shed the brightness of your light upon the nations, so that they may please you in unity of fait