Jon Bloom, in his post, Lay Aside the Weight of Self-Preoccupation:
The state of your soul depends on what occupies your mind…. The soul does not find satisfaction in the self. It’s not designed to.
…We never find in ourselves what we’re looking for. [This] frequently leads to discouragement…. Ironically, we are then often lured into self-centered introspection, which leads us into a vicious cycle of self-improvement efforts, self-indulgence, self-disillusionment… etc.
Image: detail from Echo and Narcissus, by J. W. Waterhouse.