DISCIPLINE. - An instrument of penance, which ordinarily consists of a set of cords or chains, small or large, simple or ending in bars and little balls of hard substances (wood, metals), used to chastise the flesh by flagellation.
The use of these and similar instruments of penance is common in the history of Christian asceticism, and is frequently recalled in the lives of the saints, constituting an exercise of spiritual perfection. The principle on which it is founded is the necessity of mortification (v.) as a means for the complete triumph of God in the soul.
The use of the d., undertaken for supernatural motives—of penance, of satisfaction, of impetration—is very meritorious. It helps to subdue the body (cf. I Cor. 9:27), to overcome carnal concupiscence, to surmount various temptations. It creates a habit of humility, which prepares the soul for special graces from the Lord, being a practical acknowledgment on the part of the penitent that he is a sinner and has need of the mercy of God, offended by sins. It nourishes the spirit of compunction and of austerity, and makes one like Christ who suffered flagellation.
Spiritual masters recommend it principally for three ends: 1) to make satisfaction for past sins; 2) to conquer oneself, that is, so that sensuality may obey reason, and all the lower parts of man may be more subject to the higher; 3) to seek and find some grace or spiritual gift, such as sorrow and weeping for sins, the intimate sense of the sorrows that Christ suffered in his Passion, the resolution of some doubt (cf. St. Ignatius of Loyola, Exerc. spir., addit. 10). Physical mortification in fact does not extirpate vices directly, almost physically or physiologically, but by inducing in the soul supernatural motives, which make it flee those vices, and by drawing from God special graces to avoid them.
Such chastisement of the flesh must, however, be regulated by discretion; one must take care that the pain be felt in the flesh, but not cause infirmity, nor hinder greater goods. Ordinarily it is advised that the flagellation not be prolonged for long. The immoderate use of such instruments of penance, if accompanied by a certain pertinacity, without or against the counsel of the spiritual director, can become an evil.
Conversely, he errs who would hold the use of the d. and of other external mortifications to be useless and would wish to suppress it entirely (cf. the doctrine of Molinos condemned by Innocent XI, Propos., 38, 39; Denz-U, 1258-59; and the condemnation of Americanism: Denz-U, 1972).