I had the privilege to attend the 2019 LCMS Convention as a lay voting delegate for New England District Circuit Three. During the convention we discussed and passed a resolution about 6 Day Creation. The resolution was very well crafted by the floor committee to avoid saying more or less than what Scripture said. When it was presented, a debate occurred on the floor about the term “natural day” as on its face, and in its plain reading, natural day means a normal 24 hour day. Some did not like this term and brought up a common argument that since the sun did not exist at the time of the first day how would you delineate a natural day? Since I did not get through the queue before debate ended I figured I would address this objection here since it is a common argument.
To begin let us go back to Genesis and read the text:
1 In the beginning, God created the heavens and the earth. 2 The earth was without form and void, and darkness was over the face of the deep. And the Spirit of God was hovering over the face of the waters.
3 And God said, “Let there be light,” and there was light. 4 And God saw that the light was good. And God separated the light from the darkness. 5 God called the light Day, and the darkness he called Night. And there was evening and there was morning, the first day.
Let us first point out that what delineates a day is evening and morning. This does not require a source of light though but rather requires that you can separate light and darkness. Evening and mornings are the boundaries you traverse between darkness and light.
We can see from Genesis that light is not traveling isotropically through out the cosmos. Rather there is a division which God puts in place. What that division is we do not know. It could be that light is all traveling in one direction and thus as the earth rotates you would have darkness as you move into the shadowed area (this is how day and night works currently). Alternately you could have one side of the universe with light and the other dark with the earth as it rotates straddling the middle. Regardless of the solution all you need to have evening and morning, from a physics point of view, is simply a rotating body with light coming from a single direction. Morning would occur as you rotate into the direction of the light, and evening would be as your rotate into the shadow of the body.
Now this may seem a completely odd state of affairs. However recall that God is in the midst of preforming the work of Creation. It is not anywhere near complete. Thus we have no idea what laws are governing the cosmos at this point. All we do know is that there was light and darkness, evening and morning when there was no source of light for the sources were made later, and that all of this occurred on the first day. As such the argument that a day is meaningless with out a Sun (or other source of light) is false.
One could argue about the length of this day, but the plain and obvious reading of the text that is in line with the usage in the rest of Scripture is that a day is a day is a day (see “The Length of the Days of Creation” Douglas Judisch, Concordia Theological Quarterly (1988) Vol. 52 Num. 4 pg. 266-271) . After all God is omnipotent, He can create the cosmos in any time scale He desires. Thus we need not jump through bizarre theories about how long a day is, or get in crazy pedantic arguments that it’s not exactly 24 hours. To do so is to have already given up on the obvious reading of the text and to import your own ideas into the text.
So please in the future do not use this argument. It is easy to disprove with a little thought. Instead consider and believe what the Word of God plainly says in Genesis, that the Lord created everything in six natural days by His omnipotent power.