A merry heart maketh a cheerful countenance: but by sorrow of the heart the spirit is broken.
– Proverbs 15:13
The word for heart is often used in Proverbs and refers primarily to the mind, but the word does mean more generally the inner being of man, involving mind, emotions, will, etc. For cheerful countenance we might say a happy face. The phrase means the inner thoughts and attitudes of a man affects his state of happiness (Proverbs 15:15; 18:14). The word for sorrow in the contrasting phrase means pain or injury. Just as cheerful can point to healthy, sorrow can point to wounded. The thoughts of pain, or dwelling on injury, could also point to harboring bitterness. The effect is to crush the spirit (Proverbs 12:25; 17:22).