1 In the beginning God created the heavens and the earth. 2 The earth was without form, and void; and darkness was on the face of the deep. And the Spirit of God was hovering over the face of the waters.
The New King James Version. Nashville : Thomas Nelson, 1982, S. Ge 1:1-2

The first part of verse 2 says that the earth was with form, and void. The Hebrew phrase is tohuw va bohuw. That same Hebrew phrase is found in Isaiah 45:18 where we read that God created the heaven and earth not in vain (not “tohuw va bohuw”). So, if Isaiah says that God didn’t create the earth without form and void, but Genesis 1:2 says that it is in that condition, then the only explanation is that it became that way between verse 1 and verse 2.

And that fits in with a lot of other scripture, too. For example, Isaiah 14 and Exekiel 28 speak about Lucifer rebelling against God and being kicked out of heaven. He and 1/3 of the angels who followed him came to earth, where he would become “the god of this world” (2 Cor 4:4). I don’t know how long it took, but during that time, the earth lost its initial beauty and became without form and void.

While we can say that man’s history from the time of Adam to present day is onliy a few thousand years, it is entirely possible that the earth is millions of years old. Who knows what life was here before Adam? Could it be that was when dinosaurs roamed the earth? Could it be that the Neanderthal Man wasn’t an ancestor of Adam, just a previous life form that was on this planet before God instituted his grand plan of making man in His image? I don’t know the answers, but I have no problem believing them at least as possibilities.