"Ashes of the Earth" is all the natural, physical beginnings of Matter, the visionless, impersonal, carnal, spiritless state of Life, from which by the mighty, transforming power of the Divine Laws of Creation God creates the flesh of the primordial Man.  

"Ashes" is a symbol of all the stages of spiritual "creation", "creation" of Man, everything that was in him before his spiritual formation as a Person - in the spiritual "Image" and "Likeness" of God.

Negative meaning

"Ashes" is a symbol of the frailty, frailty, short-lived corruptible, carnal, earthly life of man.

"Ashes" is a symbol of a sinfully living man, satisfying only the purely corporeal, sinful needs of his flesh. 

"Ashes" is also a symbol of all that is produced by sinfully living man, all that is not in accordance with God's Covenants, Commandments, an image of that which has no spiritual value, future, will not be used by future generations of righteously living people.