For it was not only a voice of gold, but it was the voice of a man whose heart was golden, reading from a book of golden words.
Cry, the Beloved Country p. 122
This is in contrast to one who has just a golden voice. The authority and heart behind the voice matter. The golden-voiced man with a bent heart or authority emanating from self or from the masses may be persuasive and it may even change a culture, but it will have no lasting value, no telos that is actually worth tying on to. It cannot because it has only the foundation of finite man or the current tide of culture. Tides go out and in on a regular basis. You may enjoy the thrill of riding a wave but the ride will come to an end—an impotent end on so many grains of sand.
But the heart of gold based on the golden words or the Truth may effect the greatest miracle of all—not changing a culture or moving the masses, but exposing the human heart to a truth that can break it and recreate it into a new creation that is now united with the power that created the universe. A power that is at the same time perfect love and justice and wisdom and righteousness.