2 Corinthians 12:4

Caught up into paradise. St. Augustine and St. Thomas Aquinas are of opinion that this third heaven and paradise are the same place, and designate the abode of the blessed. In order to understand the language of the apostle, we must observe that the Hebrews distinguished three different heavens. The first comprised the air, the clouds, &c. as far as the fixed stars. The second included all the fixed stars; and the third was the abode of Angels, in which God himself discovered his infinite glory, &c. The first is called in Scripture simply the heavens, the second the firmament, and the third heaven the heaven of heavens. (Calmet)