The narrower, then, the sphere of action of this second and only (remaining) repentance, the more laborious is its probation; in order that it may not be exhibited in the conscience alone, but may likewise be carried out in some (external) act. This act, which is more usually expressed and commonly spoken of under a Greek name, is ἐξομολόγησις , whereby we confess our sins to the Lord, not indeed as if He were ignorant of them, but inasmuch as by confession satisfaction is settled, of confession repentance is born; by repentance God is appeased.
…All this exomologesis (does), that it may enhance repentance; may honour God by its fear of the (incurred) danger; may, by itself pronouncing against the sinner, stand in the stead of God’s indignation, and by temporal mortification (I will not say frustrate, but) expunge eternal punishments.
Tertullian
On Repentance
Chapter IX