Interpretation:
Digging the root refers to going through the path of the heart. When your heart brings upon inconveniences in your life (reap what we sow), if you do not act on your evil thoughts (greed, arrogance, regret….), then one can purify one’s mind. This is a difficult task like digging a root. But when one is persistent in following this path of the heart, one can return to having a mind like the “Original mind” at the creation of human beings.
Heaven's Truth of the Heart, Mind, & Body 