A glad heart makes a cheerful countenance, but by sorrow of heart the spirit is broken. The mind of him who has understanding seeks knowledge and inquires after and craves it, but the mouth of the [self-confident] fool feeds on folly. All the days of the desponding and afflicted are made evil [by anxious thoughts and forebodings], but he who has a glad heart has a continual feast [regardless of circumstances].
(Proverbs 15:13-15 - AMP)