What is the meaning of “and the earth was without form (invisible), and void” (Gen. 1:2)?

St. Basil says, “‘The Earth was Invisible and Unfinished’ … it may be because man, the spectator, did not yet exist , or because being submerged under the waters which overflowed the surface, it could not be seen, since the waters had not yet been gathered together into their own places, where God afterwards collected them, and gave them the name of seas … However, as light did not yet exist, and as the earth lay in darkness, because of the obscurity of the air above it, it should not astonish us that for this reason Scripture calls it ‘invisible.’”⁴³⁶