The Hebrew word yom, day, is used 2301 times in the Old Testament. We know precisely in what sense the word is used everywhere, except, of course, in Genesis 1.
Sometimes the word means "time" in the day of the Lord" or "in the day(s) of the Judges" where the word is not plural in Hebrew, the word means "time"
So how do we determine when the word means a literal 24 hour period? Outside of Genesis 1,
The word is used 410 times with the word day PLUS A NUMBER, and it always means a 24 hour period.
The word yom is used WITH EVENING AND MORNING 38 times, and always means a 24 hour period.
It is used WITH MORNING 23 times and WITH EVENING 23 times and each time it means an ordinary day.
The word day is used WITH THE WORD NIGHT 52 TIMES and each time it means a 24 hour day.
To sum up, outside of Genesis 1, yom means 24 hours when it is used with a number (six days), whenever the phrase "evening and morning" or "evening" or "morning" is used with yom, and whenever the word is used with the word night.
No one ever questions whether Joshua might have marched around Jericho for 100,000 years or millions of years because day with a number always means a 24 hour period or daylight period.
What if we apply these tests to Genesis 1, we have in Genesis 1: 5, night, evening, morning number, 1:8, evening, morning, number, 1:13, evening morning number, 1:18, evening, morning, number, 1:23, evening morning number, and 1:31, evening morning number.
So God's intention is clear.
I say 24-hour period, although an actual earth day is 23 hours 56 minutes and 4 seconds.
Genesis 2: 1 Thus the heavens and the earth were finished, AND ALL THE HOST OF THEM. 2 And on the seventh day (yom, with qualifiers) God FINISHED his work that he had done, and he rested on the seventh day from all his work that he had done. 3 So God blessed the seventh day and made it holy, because on it God rested from all his work that he had done in creation.
That is part of the Scriptural evidence for a single 6-day creation week, about 6,000 years ago.
