If you know this, of course I will add ur best answer!!!!!!?

I guess you could interpret it that way. I read it differently though. Instead of it saying something like "while the earth was formless and empty ...", I read it as "at this time, the earth was formless and empty ...". In my interpretation Now is an adverb. It makes sense because you can replace Now with other adverbs and the sentence still makes sense, for example "suddenly the earth was formless and empty ..."