The Institutes, Book 8
Righteous or Unrighteous, Anger Blinds
From almost any cause the feeling of wrath boils over. It blinds the eyes of the soul, and by laying the deadly beam of a worse disease over the keenness of our sight, it keeps us from seeing the sun of righteousness. It makes no difference whether plates of gold, or of lead, or of any metal you please, are laid over our eyelids; the value of the metal makes no difference to our blindness.