A line from the incredible song known as Komm Süsser Tod. The meaning of this particular line runs quite deep:
It reminds us that everything we touch, see, taste, feel, love, or hate will eventually -- one way or the other -- fade away and turn to dust, nothingness.
This can be interpreted on a grand scale; such as our sun, Sol. It, too, will eventually fade to nothing, leaving a dead, black, core. The Earth will have since long been destroyed, along with everything on it. Humanity, and all it has accomplished, will die.
Perhaps even the galaxy, universe, or reality of any form will cease to exist.
On a smaller scale, it represents everything we do. Batteries run dry, natural resources are being used up, human beings die, projects which we have started will crumble and become obsolete. Thoughts expire, buildings and records are destroyed.
Thus, it will all return to nothing. A void.
See also /dev/null.