Meaning of "There is no newe guise, but it was old" in Chaucer's Canterbury Tales

The phrase "There is no newe guise, but it was old" is from the Wife of Bath's tale in Geoffrey Chaucer's The Canterbury Tales.

It's more common rewording in modern English is "There's never a new fashion but it's old".

The phrase itself appears in the following section of the tale where the Wife of Bath describes how "every lusty knight" would dress "T' fight for a lady":

Some will be armed on their legges weel;
Some have an axe, and some a mace of steel.
There is no newe guise, but it was old.
Armed they weren, as I have you told,
Evereach after his opinion.

The meaning is that nearly all ideas come around again and there are few ideas that are genuinely new and fashion, as with ideas, is cyclical. Some are forgotten, some reinvented and some simply recycled over time.

Wife of Bath's Tale, Ellesmere manuscript, c. 1405–1410