Proverbs 29:11
“A fool uttereth all his mind: but a wise man keepeth it in till afterwards.”
“A fool always loses his temper, But a wise man holds it back.” – NASB
Have you ever been around someone who has a “short fuse?” It is like you are walking on broken glass in socks. You can walk carefully for a while, but if you make one slip a shard will make its way into your foot. You can be talking with your short-tempered friend like you would any other day, but if you mention something he doesn’t like then he could transform into the Tasmanian Devil (Taz) from Loony Tunes. 
Then there is the wise man. This is the kind of person that can be insulted and walk away, or when something bad happens is willing to hold back his anger in order to comprehend the situation. When you are with this kind of person you can relax.
Are you the self-controlled wise man, or are you the short-fused fool? Can you relate to Mr. Miyagi (the quiet sensei from Karate Kid), or do you act like the Hulk? Are you slow to anger like a sloth is slow to do anything at all, or are you easily provoked like an army of fire ants?
“[Be] quick to hear, slow to speak and slow to anger; for the anger of man does not achieve the righteousness of God.” – James 1:19-20 NASB