A musician cannot move others ...

A musician cannot move others unless he, too, is moved.
 Carl Philipp Emanuel Bach

Quotes from the same author

What comprises good performance? The ability through singing or playing to make the ear conscious of the true content and affect of a composition.
 Carl Philipp Emanuel Bach
A musician cannot move others unless he too is moved. He must of necessity feel all of the affects that he hopes to arouse in his audience, for the revealing of his own humour will stimulate a like humour in the listener.
 Carl Philipp Emanuel Bach
Keyboardists whose chief asset is mere technique . . . more often than not astound us with their prowess without ever touching our sensibilities. They overwhelm our hearing without satisfying it and stun the mind without moving it.
 Carl Philipp Emanuel Bach