All therefore whatsoever they bid you observe, that observe and do; but do not ye after their works: for they say, and do not.
For they bind heavy burdens and grievous to be borne, and lay them on men's shoulders; but they themselves will not move them with one of their fingers.
And he said, Woe unto you also, ye lawyers! for ye lade men with burdens grievous to be borne, and ye yourselves touch not the burdens with one of your fingers.
"He needs to practice what he preaches."
William Langland, Piers Plowman (1377)