Isaiah 1:22 - Ellicott's Commentary On The Whole Bible

Thy silver is become dross... — The two images describe the degeneracy of the rulers to whose neglect this disorder was due. (See Notes on Jeremiah 6:28-30.) Hypocrisy and adulteration were the order of the day. The coinage of judgment and justice was debased; the wine of spiritual life (Proverbs 9:5), of enthusiasm and zeal for good, was diluted till it had lost all power to strengthen and refresh. In “the salt that has lost its savour” of Matthew 5:13 we have a like symbolism.