A set phrase used to introduce a quote from Confucius in the Analects; Confucius says

To give something a fine-sounding name despite it being inaccurate or dishonest, often used to whitewash or gloss over something negative.

(literary) used to introduce a poem or a verse, meaning "as the poem says" or "the verse goes as follows"

(literary) to be known as; named; called

some say; it is said by some