Tertullian — On Repentance 9
Of this second and single repentance: the narrower the work, the harder the proof — so that conscience alone is not enough, but some act must also carry it out. That act, more often spoken and practiced under its Greek name, is exomologesis: by it we confess our fault to the Lord, not as to one who does not know, but insofar as satisfaction is set in order by confession, repentance is born from confession, and God is softened by repentance.
So exomologesis is the discipline that lays a man low and humbles him. It enjoins a way of life that draws mercy — even in dress and diet: to lie in sackcloth and ash, to darken the body with dirt, to cast down the mind with grief, to change by sad handling the things that sin; to take food and drink simply — not for the belly but for the soul; often to feed prayers with fasts, to groan, weep, and roar day and night to the Lord your God, to fall at the elders' feet, to kneel at God's altars, and to bid all the brothers carry the embassy of one's plea.
All this is exomologesis: to commend repentance, to honor the Lord out of fear of danger, to act in the sinner himself as God's indignation, and by a temporal affliction not merely to frustrate eternal punishments but to wipe them out. When it rolls a man down, it more relieves him; when it makes him foul, it more returns him clean; when it accuses, it excuses; when it condemns, it absolves. As much as you have not spared yourself, so much — believe it — God will spare you!
Latin
IX. [1] Huius igitur paenitentiae secundae et unius quanto in arto negotium est tanto operosior probatio ut non conscientia sola praeferatur, sed aliquo etiam actu administretur. [2] Is actus, qui magis Graeco vocabulo exprimitur et frequentatur, exomologesis est qua delictum nostrum domino confitemur, non quidem ut ignaro, sed quatenus satisfactio confessione disponitur, confessione paenitentia nascitur, paenitentia deus mitigatur. [3] Itaque exomologesis prosternendi et humilificandi hominis disciplina est conversationem iniungens misericordiae inlicem, de ipso quoque habitu atque victu:
[4] mandat sacco et cineri incubare, corpus sordibus obscurare, animum maeroribus deicere, illa quae peccant tristi tractatione mutare; ceterum pastum et potum pura nosse, non ventris scilicet sed animae causa; plerumque vero ieiuniis preces alere, ingemiscere, lacrimari et mugire dies noctesque ad dominum deum tuum, presbyteris advolvi, [et] aris dei adgeniculari, omnibus fratribus legationem deprecationis suae iniungere. [5] Haec omnia exomologesis, ut paenitentiam commendet, ut de periculi timore dominum honoret, ut in peccatorem ipsa pronuntians pro dei indignatione fungatur et temporali afflictatione aeterna supplicia non dicam frustretur, sed expungat. [6] Cum igitur provolvit hominem, magis relevat; cum squalidum facit, magis emundatum reddit; cum accusat, excusat; cum condemnat, absolvit: in quantum non peperceris tibi, in tantum tibi deus, crede, parcet!