 Deal with them righteously and protect us that try to serve you. That's what he's trying to get across. He says, They return at evening. They make a noise like a dog and go round about the city. Behold, they belch out with their mouths. Swords are in their lips. For who say they doth hear? Now notice that they're even using their lips. They're using their mouth to try to bring this man down. They're trying to destroy him.