There are times that unless you have the gift of being a peace maker (which Jesus calls blessed) it would be better not to get in the middle of two people who are quarreling. Verse 19 speaks of deception. It is bad enough to see it in a world setting, but far worse to see it in a church setting, and we do sometimes. It is difficult to deal with. The typical statement of wood to a fire, is that to add fuel to strife makes relationships hotter but where fuel is withheld, the fire goes out. When we approach a quarrel, don't add to it but we need to do our best to contain it.
This whole grouping of verses is about relationships. For instance, words of a talebearer are as wounds. This is someone who tears another apart with their lips. There is the thought of digging a pit for the demise of someone else and falling in it, or rolling a stone to injure someone else. With such tactics we will eventually harm ourselves. There is that old statement: what goes around comes around. I must confess I don't know the history of that statement. The last statement is about a lying tongue hurting those that are afflicted by it. Lies affect everyone.