Canon 5: “It seemed good that whosoever should say that the grace of
justification was given to us only that we might be able more readily by
grace to perform what we were ordered to do through our free will; as if
though grace was not given, although not easily, yet nevertheless we
could even without grace fulfill the divine commandments, let him be
anathema.
For the Lord spoke concerning the fruits of the commandments when he
said: “Without me you can do nothing' (John 15.5), and not 'Without me you
could do it but with difficulty.’”