Feast of the Holy Martyr Thalleleus
THERE ARE eight general and basic categories of thoughts in which are included every thought. First is that of gluttony, then impurity, avarice, sadness, anger, acedia, vainglory, and last of all, pride. It is not in our power to determine whether we are disturbed by these thoughts, but it is up to us to decide if they are to linger within us or not and whether or not they are to stir up our passions.
The thought of gluttony suggests to the monk that he give up his ascetic efforts in short order. It brings to his mind concern for his stomach, for his liver and spleen, the thought of a long illness, scarcity of the commodities of life and finally of his edematous body and the lack of care by the physicians. These things are depicted vividly before his eyes. It frequently brings him to recall certain ones among the brethren who have fallen upon such sufferings. There even comes a time when it persuades those who suffer from such maladies to visit those who are practicing a life of abstinence and to expose their misfortune and relate how these came about as a result of the ascetic life.
—Evagrius of Pontus, The Praktikos