Foolish is as foolish does. Don’t become involved with foolishness.
Read: Proverbs 26:4
“Don’t answer the foolish arguments of fools, or you will become as foolish as they are.”
http://bibleresources.bible.com/passagesearchresults2.php?tp=31&book_id=24&c=26&passage1=Proverbs+26%3A4&version1=51