hmmm I don’t quite follow your reasoning.
Laughter is a verb which denoted a physical response normally to an emotion but also can be provoqued by tickles for example.
Some people laugh because of stress, google “nervous laughter” but most commonly because something has triggered the response. A funny story maybe.
Humor on the other hand is a noun, it describes an animic state. If someone is angry or happy it affect the person’s humor.
It is also used to describe what CAN incite most persons to laugh.
Sometimes the means of trigerring this, may even be sinful. Why a sinful situation may elicit laughter GOD only knows, but it is true it happens.
I doubt though that you can say that laughter per se is sinful, rather it is the uncharitable situation that trigerred the laughter the one we should guard against.
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