The identity of the “thorn” in Paul’s flesh has often been debated, and there are several possibilities regarding its nature. The most commonly accepted interpretation is that the thorn Paul suffered was some kind of physical weakness or “infirmity.” Supporters of this view often point out that Paul mentions the large letters he used in writing to the Galatians (Galatians 6:11), and he also mentions that the Galatians would have plucked out their own eyes and given them to him (Galatians 4:13-15) – both of which might indicate an ongoing physical eye problem.
But Paul also says in verse 13 of Galatians 4 that his weakness was “at first” – which gives the impression that it was a temporary thing from which he recovered (very possibly the stoning Paul suffered in Galatia that he describes in the same chapter ). Additionally, weakness or infirmity need not mean a physical ailment in 2 Corinthians 12:9–10. In 2 Corinthians 11:30, Paul uses the same terminology of “glorying in weakness” that he uses a few verses later in speaking about the thorn he was given. In fact, in the earlier chapter Paul lists a number of “weaknesses” he had suffered – such as imprisonment, whippings, shipwrecks, and stonings – but does not mention any specific physical ailment (2 Corinthians 11:23–29).
So, many scholars prefer to look for another explanation of Paul’s thorn in the flesh. All of the things listed in 2 Corinthians 11 as weaknesses or infirmities are forms of persecution and, in context, Paul’s thorn could have been ongoing persecution that was stirred up against him and which prevented him from fully doing the work he wished to do. In fact, the description of persecution as a “thorn” is found several times in the Old Testament. In Numbers 33:55; Joshua 23:13; and Judges 2:3, enemies of Israel are spoken of as being “thorns in your sides” and “thorns in your eyes.”
In Paul’s case, the apostle elsewhere mentioned Alexander the coppersmith (2 Timothy 4:14), Hymenaeus, and Philetus (2 Timothy 2:17), and others as persecuting him and hindering his work, so he may have had people like them in mind as being “thorns” to him and adversaries of the gospel.
Understood this way, Paul asked God to remove ongoing persecution from him, not sickness, and was told that God’s grace or help is with us in those situations – that we are sometimes not redeemed from persecution, just as Paul himself stated when he later wrote, “everyone who wants to live a godly life in Christ Jesus will be persecuted” (2 Timothy 3:12).
But the Bible does not precisely identify Paul’s thorn in the flesh. Many commentators simply gloss over this fact by saying the nature of Paul’s thorn does not matter or God would have recorded it so we would know what it was. But there is a far simpler and more likely understanding of Paul’s failure to identify what troubled him. Paul may have been intentionally vague because God inspired him not to directly identify his thorn so that people with various physical and spiritual problems could identify with Paul and understand his point in mentioning his suffering – that we can all experience the same grace that Paul did, because Christ’s power “is made perfect in weakness” (2 Corinthians 12:9) – whatever our weakness or infirmity might be.