Envy is an acute sense of separation from the blessings of Heaven, be it Power, Wealth, Knowledge or Pleasure.
Focusing on the separation, i.e. on the nature of envy, draws the soul to heaven, from which it turned in unconsciousness, and thus heals it.
Having seen the moon, the Snake was filled with bitterness.
“You are shining in the clear sky and you may hide your radiance not. But I’m hiding myself in ground and rocks, fearing to be noticed,” she said with envy. “Console yourself,” said the Nightingale to the Snake while sitting at the safe distance. “The moon shines by another’s light, but your envy, though poisonous, has its own nature.”
Envy is a loss of your own Path.