"Above all else, guard your heart, for it is the wellspring of life!" Proverbs 4:23
See that your chief study is about your heart: it is there that God's image is planted, that His interests are advanced, that the world and flesh are subdued, that the love of every sin is cast out, and that the love of holiness grows.
"I, the Lord, search the heart and examine the mind!" Jeremiah 17:10
- Jonathan Edwards