>>It is supported exactly by the verses in focus, since it is not possible to reveal of what sort the work is until it is completed.<<
I disagree. It says it will be revealed. Revealing is not cleansing. It is not purification. One does not get purified of anything other then through the shed blood of Jesus.
Revealing is not cleansing
No, by itself it is not. No one argued it is. Burning of stubble and hay, however, is cleansing as well as revealing, and yes, that is possible because Jesus died and rose again.