What word or phrase does your mother always say?
"utterance, recitation, action of the verb 'say,' " c.1300, verbal noun from say (v.); meaning "something that has been said" (usually by someone thought important) is from c.1300; sense of "a proverb" is first attested mid-15c.
Ça va sans dire, a familiar French locution, whose English equivalent might be "that is a matter of course," or "that may be taken for granted." But recently it has become the tendency to translate it literally, "that goes without saying," and these words, though originally uncouth and almost unmeaning to the unpractised ear, are gradually acquiring the exact meaning of the French. [Walsh, 1892]