An Explanation of Luther's Small Catechism · Martin Luther
A RIGHT HEART.
THE HEART BY NATURE SINFUL. We are born with a sinful nature and a natural inclination to evil (Original sin), which we have inherited from our ancestors as a result of the fall into sin. [John 3:6+, Jer. 17:9] This natural inclination to evil manifests itself in wrong thoughts and desires which arise in the heart. [Rom. 7:18, 19+] These wrong desires or lusts are in themselves sinful: and if they are not subdued, they lead to sins of words and deeds. [Jas. 1:14, 15+] These commandments _forbid_ us to covet anything that is our neighbor's. They _command_ us to assist and serve him in retaining his own.
Text from Project Gutenberg, public domain in the United States.