"...and a night shall be as a thousand years...." Same book, different verse.
Psalm 90:4 "For a thousand years in your sight are like a day that has just gone by, or like a watch in the night."
2Peter 3:8 "But do not forget this one thing, dear friends: With the Lord a day is like a thousand years, and a thousand years are like a day."
Now consider Genesis 1:
5: "God called the light "day," and the darkness he called "night." And there was evening, and there was morning—the first day.
" 6 And God said, "Let there be an expanse between the waters to separate water from water." 7 So God made the expanse and separated the water under the expanse from the water above it. And it was so. 8 God called the expanse "sky." And there was evening, and there was morning—the second day....
"11 Then God said, "Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds." And it was so. 12 The land produced vegetation: plants bearing seed according to their kinds and trees bearing fruit with seed in it according to their kinds. And God saw that it was good. 13 And there was evening, and there was morning—the third day.
14 "And God said, "Let there be lights in the expanse of the sky to separate the day from the night, and let them serve as signs to mark seasons and days and years, 15 and let them be lights in the expanse of the sky to give light on the earth." And it was so.
16 God made two great lights—the greater light to govern the day and the lesser light to govern the night. He also made the stars. 17 God set them in the expanse of the sky to give light on the earth, 18 to govern the day and the night, and to separate light from darkness. And God saw that it was good. 19 And there was evening, and there was morning—the fourth day.
So, the "evening and...morining" of Genesis are pretty clear. On the other hand, both the Old and New Testaments tell us that a day for God can be a thousand years for us.
And, we must consider this: whereas plants and trees come on the third day, the sun and moon don't arrive until the fourth day. So clearly the "evening and...morning" of those early days have nothing to do with rising and setting of the sun, I'd suppose...