Self-love, as has often been said, is the cause of all impassioned thoughts. For from it are produced the three principal thoughts of desire; those of gluttony, avarice and self-esteem. From gluttony is born the thought of unchastity; from avarice, the thought of greed; from self-esteem, the thought of pride. All the rest–the thoughts of anger, resentment, rancor, listlessness, envy, backbiting and so on–are consequent upon one or other of these three. These passions then, tie the intellect to material things and drag it down to earth, pressing on it like a massive stone, although by nature it is lighter and swifter than fire….
The origin of all the passions is self-love; their consummation is pride. Self-love is a mindless love for the body. He who cuts this off cuts off at the same time all the passions that come from it….
He who desires earthly things desires either food, or things which satisfy his sexual appetite, or human fame, or wealth, or some other thing consequent upon these. Unless the intellect finds something more noble to which it may transfer its desire, it will not be persuaded to scorn these things completely. The knowledge of God and of divine things is incomparably more noble than these earthly things.
~St Maximos the Confessor