38. Guard What Is Most Worth Guarding
Epictetus names the thing most worth guarding, and asks you to guard it with the same care you give your foot.
As, in walking, you take care not to step on a nail or turn your foot, so, in the same way, take care not to hurt the ruling part of your mind.
If we guarded against this in every action, we would take up each action with greater safety.
What this means. You watch where you put your feet. Watch where you put your mind with the same care.