Proverbs 14:13 "Even in laughter the heart is sorrowful; and the end of that mirth is heaviness."
Dr. Peter Ruckman: "The kind of mirth propagated by radio and TV comedians, and the kind of mirth panhandled by skeptics and infidels produces heaviness. This is apparent from a collection of 'deathbed' testimonies of famous men. They do not laugh at sin, death, hell, God, or the Bible ON THEIR DEATHBEDS. 'He that sitteth in the heavens' laughs last, and He who laughs last laughs best."
Ecclesiastes 7:5-6 "It is better to hear the rebuke of the wise, than for a man to hear the song of fools. For as the crackling of thorns under a pot, so is the laughter of the fool..."