Basil on repentance
From the letters of St Basil (330-379 AD)
Make the effort to rise from the ground. Remember the good Shepherd who will follow and rescue you. Whether you are wounded in both legs, or only in a lobe of an ear, spring back from the beast that has wounded you.
Remember the mercies of God and how He cures you by pouring on oil and wine. Do not despair of salvation. Recall your memory of how it is written in the Scriptures, that he who has fallen rises, and he who turns away returns; the wounded one is healed, the prey of wild beasts escapes; he who confesses his sin is not rejected. The Lord does not desire the death of a sinner but rather that he should turn and live.
Do not despair, like the wicked in the pit of evil. There is a time of endurance, a time of long suffering, a time of healing, a time of correction. Have you stumbled? Arise. Have you sinned? Cease. Do not stand in the company of sinners, but spring away. When you are converted, and groan in sorrow for your sins, you shall be saved.
Out of labor comes health, out of sweat comes salvation from your sins that bind you. Beware, so that when you strive to keep certain obligations, you do not break the obligations to God which you professed before many witnesses. Everyone is ready to welcome you; everyone will share your efforts.
Do not sink back. Remember the days of old. There is salvation; there is renewal. Be of good cheer; do not despair. It is not a law condemning you to death without pity, but mercy that puts away punishment and awaits improvement. The doors are not yet shut; the Bridegroom hears you. Sin is not the master.
— St. Basil the Great, from letter 44