Thus the heavens and the earth were finished, and all the host
of them. 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. 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
The Number Seven has two fundamental symbolic meanings in Scripture:
1) Completeness, Fullness, or Perfection
2) To Swear, to Vow, to make an Oath
This is discussed at length in the article called Seven and Scripture.
The identities below are but few of the more spectacular examples of how the
Number Seven modulates between a concept and the manifestation
of its perfection or completeness.