Even in laughter the heart is sorrowful; and the end of that mirth is heaviness.
– Proverbs 14:13
[T]his proverb is a wise observation. Our emotional circumstances change, and can change quickly. As we grow in wisdom, we are more aware that joy and sorrow are mingled together (Ecclesiastes 1:18). The wisdom taught here instructs us not to put too much by our present experience. For good or bad, it will change, and probably soon.