Jokes or humor in talks from the platform are discouraged.

School Guide Book study 31 p. 193, Respect Shown to Others, says.

"Resist the temptation to make witty remarks just for the sake of making the audience laugh. This detracts from the dignity of the Bible’s message. True, we should take delight in our service to God. There may even be facets of our assigned material that are somewhat humorous. Yet, to reduce serious matters to laughing matters betrays a lack of respect for the audience and for God."

This is especially hard for some of the brothers because the Witness theology is so freaking hilarious.