We all know the feeling we have for something when we have an investment in it. People always try to protect their investment. This is natural. Here we find a rejection of the world, not in an absolute sense, but in a relative sense. The world in itself is valuable only when it is seen in its relationship to God.
Food is the most obvious example.
Everyone agrees that eating, after breathing, is the most necessary and normal activity of our life. That is, it is abnormal as it now exists apart from God's love. All of these are then signed with a question mark. Inasmuch as the world is treated as normal, because this is in fact all we know, and inasmuch as it is not normal or truly worldly in the Christian sense, then it is a deception and a lie, and we must tell it as it is. In a real sense the Church, in asking her people to fast, is declaring a moratorium on the world.