This long list of relatively short quotations has been collected over many years by Glenda Taylor.  Scroll through to see them all.  They are all credited appropriately, so feel free to copy and use in your own work.

“If one has, indeed, done deeds of wickedness, but afterward alters his way and repents, resolved not to do anything wicked, but to practice reverently all that is good, he is sure in the long run to obtain good fortune—this is called changing calamity into blessing.”  Taoism.  Treatise on Response and Retribution

“In proportion as a man who has done wrong, himself confesses it, even so is he freed from guilt, as a snake from its slough.  In proportion as his heart loathes his evil deed, even so far is his body freed from that guilt.” Laws of Manu 11.228-30

“How differently shall we then incline our wills toward the will of God!  His will is for us to desire truth, whereas we desire falsehood; His will is for us to desire the eternal, whereas we prefer that which passes away; His will is for us to desire great and sublime things, whereas we desire the base things of earth;  Hew oudl have us desire only what is certain, whereas here on earth we love what is doubtful.  What a mockery itall is, my daughters, unless we beseech God to deliver us from these perils for ever and to keep us from all evil!  And although our desire for this may not be perfect, let us strive to make the petition.” Christianity, St. Teresa of Avila, The Way of Perfection.

“Whosoever looks upon his wrongdoing as wrongdoing, makes amends by confessing it as such and abstains from it in the future, will progress according to the Law.” Buddhism.  Digha Nikaya i.85, Samannaphala Sutta

“You should become the person who prays as follows: “All the sins of the past and present are my responsibility.  Father!  Forgive me!” Unification Church, Sun Myung Moon, 2-21-60

“As was the will of God, so I ought to have thought;  As was the will of God, so I ought to have spoken;  As was the will of God, so I ought to have acted.  If I have not so thought, so spoken, so acted, Then do I repent for the sin, Do I repent by my thought, word, and deed.  Do I repent with all my heart and conscience.” Zoroastrianism.  Pater 6

“The sin which makes you sad and repentant is liked better by the Lord than the good deed which turns you vain and conceited.”  Islam.  Nahjul Balagha, Saying 44

“Let us rid ourselves of evil doing, Let every person ask pardon of the Great Light Asis, The molder of us all, Who has given us this land to inhabit, and to multiply in.” African Traditional Religion, Kipsigis Poem, Kenya

“The sacrifice acceptable to God is a broken spirit;  a broken and contrite heart, O God, thou wilt not despise. “  Judaism and Christianity.  Psalm 51.17

“Truly God loves those who repent, and He loves those who cleanse themselves.” Islam.  Qur’an 2.222

“I used to watch butterflies.  I used to watch the snakes…Now today, we don’t have a heart.  We’re just empty.  We’re just like a robot.  We’re not even alive… Grandfather said, “All you own is your birth and your death.  That’s all you have.  Just think of that.  You don’t have nothing.  You can have millions of dollars, you have millions of diamonds, millions, what good is it going to do you? ..The Great Spirit will help us.  We will never be without.” Native American, Juanita Centeno, Chumash, Wisdom’s Daughters

“Great is repentance; it turns premeditated sins into incentives for right conduct.”  Judaism.  Talmud, Yoma 86b

“The (person seeking a vision) cries, for he is humbling himself, remembering his nothingness in the presence of the Great Spirit.”  Native American, Black Elk, Sioux Tradition

“The fool who knows that he is a fool is for that very reason a wise man;  the fool who thinks he is wise is called a fool indeed.” Buddhism.  Dhammapada 63