The most powerful weapon of the devil is despair. He doesn’t rejoice nearly so much when we sin as he does when we despair. This is because the final and definitive victory of the devil is when he succeeds in casting the soul into despair.
That’s why we must remember that God always has an open door, an open window for us. Always. All we have to do is keep on progressing towards his countenance.
Based on St. John Chrysostom, St. Augustine