I suspect it’s mostly a justification for the authority of whatever language the author who first wrote it used himself.
Not that it is a strong argument, but I don’t see any culture today feeling a need to justify their language. I suppose it arises when the Jews’ claim to have a covenant with God is seen as being outrageous and requiring justification. From that perspective, holy scripture is a collection of stories whose purpose is to bring a people together, defining who they are morally and historically by a shared mythology passed on through the ages. While the Torah, the Bible does serve that function, it is secondary to that which the church proclaims. It is the inspired revelation of the Word of God.
Coincidentally, yesterdays Gospel reading was:
They said, “Where did this man get all this?
What kind of wisdom has been given him?
What mighty deeds are wrought by his hands!
Is he not the carpenter, the son of Mary,
and the brother of James and Joses and Judas and Simon?
And are not his sisters here with us?”
And they took offense at him.
Knowing Jesus as a carpenter, a son and brother rendered them incapable of seeing Him as prophet, king, priest and brother to all, as the first Son of God the Father within the Trinity. They did not see Him because they thought they knew Him. The sacred is present in every moment, hidden in our daily lives, by our “daily lives”.
There are too many ongoing incidents where what seemed unintelligible in scripture is found to contain a depth of meaning and truth. It is unwise to leave it at a surface level. I firmly believe that Genesis is literally true. The problem is finding the key that will open it up to reason. That key is a Light that illumines our darkness, the Light that is Jesus Christ, through the grace of the Holy Spirit.
We name, classify, and analyse things as one of the key aspects of our nature that define us as human beings. A name identifies an object and its character. It is an expression of authority. Doctors provide a diagnosis and in doing so allow us to transcend our ailments and pursue healing, the peace that follows acceptance, if no cure is possible. Reality exists as a system of events that exist as themselves. That order and the capacity to grasp it, is established by God at the beginnings of creation.The name given by a person fixes a set of associations in the mind to the particular object, whose reality, what it is in its context, is given by God through the name He assigns.
A few more points come to mind. The idea of the creation of light at the beginning before that of the sun is consistent with the understanding that physics provides. The speed of light is at the centre of what constitutes space and time, as the constant around which both are measured. You don’t need the relationship between the sun and the earth to separate light from darkness. What we call “day” and “night” would be an abstraction of what they mean, projected onto the diurnal variations of sunlight resulting from the rotation of the earth. The words describe a state of being.