The Bible writes that for every day of creation there was “evening and morning” for each respective day:
Genesis 1:5 King James Version (KJV)
5 And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
The 7th day of the week was the last day of the week, where God rested on it and did no work on it:
Genesis 2:3-4 King James Version (KJV)
2 And on the seventh day God ended his work which he had made; and he rested on the seventh day from all his work which he had made.
3 And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made.