One of the greatest fallacies of our faith, and actually one of the greatest acts of unbelief, is the thought that our spiritual acts and virtues need to be advertised to be known. The frantic efforts of religious personages and groups to advertise and certify themselves is a stunning revelation of their lack of substance and faith. Jesus, surely with some humor, remarked that a city set on a hill cannot be hid (Matt. 5:14). I would not like to have the task of hiding Jerusalem, or Paris, or even Baltimore. The Gospel stories tell us how hard Jesus and his friends tried to avoid crowds and how badly they failed. Quite candidly, if it is possible for our faith and works to be hidden, perhaps that only shows they are of a kind that should be hidden. We might, in that case, think about directing our efforts toward the cultivation of a faith that is impossible to hide (Mark 7:24).
Dallas Willard, The Spirit of the Disciplines, 173.