In 2 Peter we read, “one day is with the Lord as a thousand years.” Now some Christians claim we can’t know how long the days in Genesis were because, well, a day is a thousand years!

But creation isn’t the context of Second Peter—the context is Jesus’ second coming and how God doesn’t view time like us. He’s outside time so a long time to us isn’t long to God.

And the verse says a day is as a thousand years—not that it is a thousand years. And, well, the rest of the verse says a thousand years is as a day. So clearly Peter is not defining the word day in Genesis for us.