Fasts and vigils, the study of Scripture, renouncing possessions and everything worldly are not in themselves perfection, as we have said; they are its tools. For perfection is not to be found in them; it is acquired through them. It is useless, therefore, to boast of our fasting, vigils, poverty, and reading of Scripture when we have not achieved the love of God and our fellow men. Whoever has achieved love has God within himself and his intellect is always with God.
Based on St. John Cassian