Genesis 1:14-18

14 Then God said, “Let there be lights in the expanse of the heavens
When the structure of the passage is given consideration, we inquire more deeply about how this second line of the fourteenth verse compares to those in verses 15 and 17, where the focus is on the giving of light on the earth. There is more implied than a merely physical aspect.

The Hebrew word translated, seasons, ( וּלְמ֣וֹעֲדִ֔ים ) validates this observation, because the appointed times relate to the holy day calendar and to prophesied events. There is a sense where the light given has to do with spiritual insight.

This interpretation finds further support in the other curiosity about the structure of this passage. See the comment in verse 16.
to separate the day from the night, and let them be for signs and for seasons and for days and years;
15 and let them be for lights in the expanse of the heavens
to give light on the earth”; and it was so.
16 God made the two great lights, the greater light to govern the day, and the lesser light to govern the night;
By reason of the symmetrical pattern, we must conclude that this compares to the second line of verse 18. This pairing really begins to make sense when we consider the metaphor where light has to do with understanding. As those such as E. W. Bullinger and Joseph A. Seiss have brought forward, the reality of Psalm 19's testimony is manifest!

1) The heavens are telling of the glory of God;
And their expanse is declaring the work of His hands.
2) Day to day pours forth speech,
And night to night reveals knowledge.
3) There is no speech, nor are there words;
Their voice is not heard.
4) Their line has gone out through all the earth,
And their utterances to the end of the world.
He made the stars also.
17 God placed them in the expanse of the heavens
to give light on the earth
18 and to govern the day and the night,
and to separate the light from the darkness; and God saw that it was good.