In your nature, eternal Godhead, I shall come to know my nature. And what is my nature? It is fire, because you are nothing but a fire of love. And you have given humankind a share in this nature, for by the fire of love you created us.
St. Catherine of SienaPenance to be sure must be used as a tool, in due times and places, as need may be. If the flesh, being too strong, kicks against the spirit, penance takes the rod of discipline, and fast, and the cilice of many buds, and mighty vigils; and places burdens enough on the flesh, that it may be more subdued. But if the body is weak, fallen into illness, the rule of discretion does not approve of such a method.
St. Catherine of Siena