o be dumb is to have the inability to speak,  and   on the other hand (looking at it in the vernacular)  it is to say something you wish you hadn’t.  In other words, there are the dumb and the   dumber.   Long before the movie by the   same name (Dumb & Dumber),  the New   Testament gave us examples of both.  
                        Jesus   exorcised a dumb demon in the eleventh chapter of Luke.  He loosed the tongue of some poor man who was   possessed by an evil spirit that made him speechless.  After a miracle, the dumb spoke.  Being able to speak is indeed a gift.  The gift of “tongue” is much more impressive   and powerful than the gift of “tongues.”    I will take what God gives me, but I would much rather have the former   than the latter.
                        Then   there is the “dumber.”  The father of the   “Voice” in the wilderness, did not believe God’s Word, even when it was   delivered  by Gabriel himself.  Zacharias was struck “dumb” until what was   predicted came to pass.   Gabriel called   the message “Glad Tidings.”  To not   believe the bad news about sin is dumb.    To not believe the good news about God’s salvation is dumber.    -id