CLAIM: Paul writes that he “was caught up to the third heaven” (2 Cor. 12:2). What is the third heaven?
RESPONSE: We don’t need to speculate too much on what Paul meant by the “third heaven.” In verse 4, he explicitly tells us that this was “Paradise.” This is the same word that Jesus used to describe heaven to the thief on the cross (Lk. 23:43). But why did Paul call it the “third heaven,” if he simply meant Paradise? In the OT, the term “heaven” had at least three different meanings:
The FIRST heaven. This refers to the atmosphere. For instance, in Genesis 1:20, the birds fly in the “expanse of the heavens.”
The SECOND heaven. This refers to outer space. For instance, in Genesis 1:17, God placed the stars and planets in the heavens.
The THIRD heaven. This refers to the dwelling place of God beyond the universe. Solomon told God, “Heaven and the highest heaven cannot contain You” (1 Kings 8:27). Since God is beyond the universe, he must dwell in some spiritual place outside of it. This must be what Paul had in mind by calling this place the “third heaven.” While Jewish interpreters during the time of Paul split the heavens into three, five, seven, and even ten different divisions, Paul kept it simple. He calls this place the “third heaven” to differentiate it from the atmosphere (the first heaven) and from outer space (the second heaven).
At the same time, many Jewish texts understood heaven to have three spheres—the third being the highest:
“I saw a third heaven far brighter than those two, for there was in it a height without bounds” (Testament of Levi 2). It goes on to describe seven heavens (Testament of Levi 3).
“Raise him into paradise, even to the third heaven” (Apocalypse of Moses 37:5).
“Those men took me from there, and they brought me up to the third heaven, and set me down |there|. Then I looked downward, and I saw Paradise” (2 Enoch 8:1).
“All things whatsoever I showed thee are in the first and second heaven, and in the third heaven the sun passes through and gives light to the world. But wait, and thou shalt see the glory of God” (3 Baruch 4:7).
 Brauch writes, “In the time of Paul some Jews made a finer distinction than that made in the Old Testament, dividing the heavens into five (3 Apocalypse of Baruch 11:1), into seven spheres (Testament of Levi 3:1; Ascension of Isaiah 9; in the Talmud b. Hagigah 11b), and into ten (2 Enoch 20:3b; 22:1).” Walter Kaiser, Peter H. Davids, F.F. Bruce, and Manfred Brauch, Hard Sayings of the Bible (Downers Grove, IL: InterVarsity, 1996), 2 Corinthians 12:2 “The Third Heaven.” Additionally, the pseudepigraphical work (The Apocalypse of Moses, 37:5) refers to the “third heaven.” Cited in Colin G. Kruse, 2 Corinthians: An Introduction and Commentary, vol. 8, Tyndale New Testament Commentaries (Downers Grove, IL: InterVarsity Press, 1987), 195.