Here's an interesting thought: When God told Noah to bring animals into the ark, he was to bring seven each of the pure animals (ones we can eat) and two each of the impure (ones we cannot eat). In this portion, God uses the word tahora for the pure animals and eininah tehorah (those that are not pure). Why didn't God just say the short word tumah (impurity) and save six letters? The rabbis say that this teaches us to always say something in a nice way. So, instead of saying: "Ow! You hurt me!" you can say: "I guess you didn't realize that doing that hurts." Or rather than saying, "You look awful," you can ask: "How are you feeling today? Can I help with something?"