John of Damascus wrote about the 7 heavens!

John of Damascus was a Christian monk, priest, hymnographer, and apologist in Damascus, Syria – living from c. 675 to 749 AD. He wrote works expounding the Christian faith, and composed hymns which are still used liturgically in Eastern Christian practice throughout the world.
His writing called “An Exact Exposition of the Orthodox Faith” is a collection of accepted theology derived mostly from theologians of the 4th and 5th centuries, providing a comprehensive overview of Christian thought.

“But if you should wish to look upon the seven zones as seven heavens there is no injury done to the word of truth. For it is usual in the Hebrew tongue to speak of heaven in the plural, that is, as heavens, and when a Hebrew wishes to say heaven of heaven, he usually says heavens of heavens, and this clearly means heaven of heaven, which is above the firmament, and the waters which are above the heavens, whether it is the air and the firmament, or the seven zones of the firmament, or the firmament itself which are spoken of in the plural as heavens according to the Hebrew custom.”
– John of Damascus [c. 675 – 749 AD]
(An Exact Exposition of the Orthodox Faith, Book 2, Ch 6)