Whoever corrects a scoffer gets himself abuse, and he who reproves a wicked man incurs injury.
Proverbs 9:7

The etymology of scoffer (luts) seems to connect scoffing with babbling nonsense. A derivative, melits, is a translator or ambassador, someone who relays a message between people of different tongues, ie who seem to speak nonsense to each other. The same connection is apparent in English when someone says "nyah nyah" or "blah blah" to mock someone else's words.

If someone is prone to mock the words of others, then correcting him will only give him fuel.