"Though the beginnings and foundations of saintliness are implanted in every person's heart, if he does not occupy himself with them, he will witness details of saintliness without recognizing them and he will trespass upon them without feeling or perceiving that he is doing so. For sentiments of saintliness, fear and love of God, and purity of heart are not so deeply rooted within a person as to obviate the necessity of his employing certain devices in order to acquire them."