Jokes and plays are words and gestures that are not instructive but merely seek to give lively pleasure. We should enjoy them. They are governed by the virtue of witty gaiety to which Aristotle refers (Ethics 1128aI) and which we call pleasantness. A ready-witted man is quick with repartee and turns speech and action to light relief.
— Thomas Aquinas, Summa Theologica, II-II, Question 148, Article 2. (Thomas Gilby translation.)
It is against reason to be burdensome to others, showing no amusement and acting as a wet blanket. Those without a sense of fun, who never say anything ridiculous, and are cantankerous with those who do, are called grumpy and rude.
— Thomas Aquinas, Summa Theologica, II-II, Question 148, Article 4. (Thomas Gilby translation.)
Actions done jestingly are not directed to any external end; but merely to the good of the jester, in so far as they afford him pleasure or relaxation.
— Thomas Aquinas, Summa Theologica, I-II, Question 1, Article 6, Reply to Objection 1. (Standard translation.)
Unfortunately, the Wesleyan tradition (beginning with dear old Mr. Wesley himself) has not taken such an approving stance toward levity.
This is truly unfortunate, since humor and laughter are, in themselves, psychologically healthy and good.
This is clearly one of several places where the Holiness tradition needs to be corrected.