The Institutes, Book 9
The Fifth Combat: Dejection
In our fifth combat we have to resist the pangs of gnawing dejection. For if, through separate attacks made at random and through chance, haphazard changes, it has found an opportunity to take possession of our mind, it keeps us back at all times from all insight in divine contemplation, and it utterly ruins and depresses the mind that has fallen from its full state of purity. It does not let the mind say its prayers with its usual gladness of heart, or rely on the comfort of reading the sacred writings, or be quiet and gentle with the brothers. It makes it impatient and rough in all its duties of work and devotion. And as all wholesome counsel is lost and steadiness of heart destroyed, it makes the feelings almost mad and drunk, and crushes and overwhelms them with a despair that is itself a punishment.