It seems to me that the works that demonstrate faith are those works that flow from faith naturally and evidently. We have faith and we’re (or should be) to action.
Salvation isn’t a payback or wages earned but rather the response of God being pleased by our faith.
As Paul said, “without faith, it is impossible to please Him well....” (Heb 10:6)
They indeed are, and in fact everyone is acting out what they really, truly believe, at least at the moment, regardless of whether it corresponds to what they profess. And every time we chose to yield to the desires of the flesh (which need not be in a “big” sin, but even lust for food) we are saying that it is Lord, but the Christian wishes he/she would never sin (thus even if they could sin in Heaven, they will not). See http://peacebyjesus.witnesstoday.org/rubornagain.html “ARE YOU BORN AGAIN?, by J. C. RYLE - 1816-1900
May our (my) consecration always match our desire, by faith.