The phrase, "And the Earth was without form, and void," points to a stupendous convulsion which affected the Earth after it was created by God.
"Without form, and void," in the Hebrew is literally, "tohu" and "bohu," which signify, "wasteness and emptiness." God did not create the Earth in this fashion. It became that way at a point in time. Many Scholars believe that Lucifer ruled the Earth after it was originally created, and did so for an undetermined period of time. As well, during that time, he ruled it in Righteousness and Holiness under God. It also seems there was a race of created beings over whom he ruled. Whenever Lucifer led his rebellion against God, one-third of the Angels, plus this race of beings threw in their lot with him. Many think, and it is probably correct, that these particular beings, whatever they might have been, are the demon spirits which presently help Satan.
Some have claimed that demon spirits are fallen angels; however, angels have spirit-bodies, whereas demon spirits have no body whatsoever, and in fact, seek s body to inhabit, whether animal or human.
I think it should be obvious that whatever degree this revolution of Lucifer was, its destructive power was beyond comprehension. Genesis 2:1
JSM Bible commentary