Do not repeat slander; you should not hear it, for it is the result of hot temper. - Ptahhotep

Do not be arrogant because of your knowledge, but confer with the ignorant man as with the learned. For knowledge has no limits, and none has yet achieved perfection in it. Good speech is more hidden than malachite, yet it is found in the possession of women slaves at the millstones.

One who is serious all day will never have a good time, while one who is frivolous all day will never establish a household.

Be a craftsman in speech that thou mayest be strong, for the strength of one is the tongue, and speech is mightier than all fighting.