v1-7 - It's hard to know what Paul's talking about in the opening verses of this chapter. Is he talking about himself or somebody else? What & where is the 'third heaven?'
A good study Bible will help you answer these questions (I recommend either Faithlife Study Bible or Reformation Study Bible, both of which are accessible online).
The general consensus is that Paul was referring to himself, that by the 'third heaven' he simply means the sky above the sky (heaven & sky are synonymous concepts in ancient cosmology), OR possibly that this whole passage is sarcastic hyperbole (which is common in Greek philosophical writings), since Paul's point here that even an amazing experience like this isn't worth boasting about.
v7b-10 - Paul never reveals exactly what the thorn in his flesh specifically was, but Paul refers to it as a blessing in his life, given to him to "keep him from becoming conceited (v7)." Although the burdens that crush you are the result of sin (either you own sin, the sin of another, or just the sinful, fallen condition of the world), these awful torments can be a blessing if they cause you to rely more and more on Christ rather than on your own strength.
v11-21 - Paul's nemesis, the "super-apostles" (literally the super-duper apostles in v11) that he's mentioned before in these letters always came to town with their hands out looking for financial remuneration. But Paul can honestly say it's not about the money, because each time either he or another missionary visited the Corinthians, they never asked for anything... financial, that is. Paul wants much more than money, he wants "not your possessions, but you (v14)." God wants every aspect of your life aligned with His will.
OLD TESTAMENT REFERENCE: In Numbers 33:55-56, God tells Israel that if they do not drive all of the heathens out of Canaan, they will forever be a "thorn in their sides."
Use the comment box below to discuss one or more of these questions:
EYE FOR DETAIL—From what you recall seeing in this chapter, try answering the following question without looking at your Bible: How did Paul complete the following sentence? “For when I am weak,…” (See verse 10.)
How would you discern whether a 'thorn' in your life was the result of sin (as the evil nations were for Israel), or a divinely ordained difficulty designed to help you realize that God's grace is sufficient?
Question 1 taken from The Complete Bible Discussion Guide: New Testament
Follow the AAA Prayer Pattern:
ACKNOWLEDGE WHO GOD IS: God's power is made perfect in your weakness (v9)
ALIGN YOUR LIFE WITH GOD'S WILL: Delight in weaknesses, in insults, in hardships, in persecutions, and in difficulties (v10), because these thorns cause you to rely more and more upon God rather than yourself.
ASK GOD FOR WHAT YOU NEED: