The Bible in Matthew 10:16 says "...Therefore be as shrewd as snakes and as innocent as doves."
How is that possible on one point we have to be so precisely clever it's almost sneaky, then on the other hand we have to be totally innocent. In other words the text is saying its OK to be wise and its OK to be smart, but not so smart that you think you're better than someone else. Our wisdom should be based in love. When it is its OK to be loving and open with anyone. We should have a cap of discipline regarding our conversations knowing when something is too much, but it's not good to be too capped. Speak your mind freely and precisely from a pure heart and let purpose guide your words. In This we can't fail.
A good tip*: Let as many of your conversations as possible be based in God. Spread Gospel, not gossip.