A man should know that a devil’s sickness is on him if he is seized by the urge in conversation to assert his opinion, however correct it may be. If he behaves this way while talking to his equals, then a rebuke from his elders may heal him. But if he carries on in this way with those who are greater and wiser than he, his sickness cannot be cured by human means.
St. John Climacus
The Ladder of Divine Ascent 4
