(Greek: austeros, harsh, rough)

Rigorous forms of corporal penance self-imposed by holy men and consisting in painful exercises or privations, such as long fasts, curtailment of sleep, abstention from lawful pleasures, flagellation, to repress and to control the animal passions. These austerities were sometimes abused; but where they were done in private and joined with a sincere attempt to acquire interior perfection, they were good. Saint Jerome wrote of them to Celantia: Be on your guard when you begin to mortify your body by abstinence and fasting, lest you imagine yourself to be perfect and a saint; for perfection does not consist in this virtue. It is only a help, a disposition, a means for the attainment of true perfection.