But just as a lump of earth is scattered when it strikes on a stone, in the same way they were scattered in all directions and perished. Therefore the gods increased and the demons diminished. He who knows this increases in himself and his enemies diminish. Satapatha Brahmana 5.1.1.1-2, p. 441. The spirit is indeed willing, but the flesh is weak.
Every person has both a bad heart and a good heart.
No matter how good a man seems, he has some evil. No matter how bad a man seems, there is some good about him. No man is perfect. Native American Religions. Qur'an 2.177, p. 861.