OK, here is how I believe it. First off lets look at a specific verse that will add meaning to this. This obiously is a whole study and covers many verses, but I will just give one of them and we can look at that.Genesis 1:28And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.The word "replenish" means to "refill". If there was never life on the earth before he would just tell him to "fill" the earth, not "refill". We also see that God told Noah the same exact thing after he destroyed the earth with water, and Noah's family was all that was left.Genesis 9:1And God blessed Noah and his sons, and said unto them, Be fruitful, and multiply, and replenish the earth.Here you see him giving the same command to Noah. He wants him to "refill" the earth since he destroyed the life on it originally.Here is what I believe, and this comes from much study by others who I have learned under, and from looking myself. I believe that there was an earth before this one, and it was inhabited by the angels and lucifer. It speaks of trafficking done by lucifer in Isaiah between the cities. Once lucifer fell, God destoyed this earth, and left it in darkness, without form and void of any life. When God created the earth as we know it now, he renewed it, and we see this in Genesis chapter 1. If you want some more verses on these thoughts then I can look for them. It will take me a little time though because its has been a while.