Where does the expression “in seventh heaven” come from and What does seventh heaven mean?

The expression “in seventh heaven” means: In a state of ineffable bliss or delight; having great pleasure.

This, especially in Islamic beliefs, is the heaven of heavens, in its literal sense, the abode of God and the highest angels.

A similar concept prevailed among the Jews in pre-Christian times, probably acquired from Babylonian beliefs.

The concept calls for seven heavens, one lying above another, graded according to the degree of merit one has acquired on earth, or, in some beliefs, according to the successive steps taken by the soul after death.