There is a principle in chapter 17 that I noticed after reading, and that is that sometimes it is better just to keep our mouth AND our ears shut.
17:4 - The wicked person referred to here is not necessarily the one who is doing the speaking, but the one who is doing the listening. Often times, Christians think they are doing nothing wrong because they did not say anything. Yet, this verse tells us we ARE a liar if we listen to those things that are not true. I believe the reason being that lies and gossip only spread as far as someone is willing to listen. As I often say, "Don't allow yourself to be someone else's trashcan. Tell them to keep their garbage to themselves."
17:14 - Solomon here gives great advice about how to handle a fight or a disagreement - walk away before it starts and gets out of hand! How many times do we feel the need to "get our point across," when really we are just giving in to our ego and trying to prove to everyone that we are right? We would have a lot less arguments and a lot more friendships still in tact if we would just quietly walk away from needless and pointless arguments.