Galatians 4:13:

Ye know how though infirmity of the flesh I preached the gospel to you at the first.

Notes on Galatians 4:13:

Obviously, Paul was healed of whatever infirmities he had.  If you had just been stoned at Lystra (which was part of Galatia where he preached “through infirmity of the flesh”), you might have had an infirmity of the flesh, too!  Thank God, it was only “at the first” because God healed Paul.  Another hint to the nature of Paul’s “infirmity” is found in Galatians 6:17 – Paul bore in his body the marks of the Lord Jesus.

That it was only “at the first” demonstrates that Paul was healed of whatever problem(s) he had.  Thus, this verse can be used as a healing Scripture, not as a “sickening Scripture” the way some would use it.

Whatever Paul’s problem was, he mentioned it as a problem only at Galatia and only “at the first.”  This trial “was” in his flesh, which proves that it did not continue as a chronic “thorn in the flesh” that Paul had to deal with throughout his ministry.

People have suggested that because Paul talked about the Galatians being willing to pluck out their own eyes and give them to him, he had some kind of chronic eye problem.  It could not have been chronic because it was only “at the first.”  It could possibly have been an eye problem resulting from Paul’s stoning at Lystra.  All we know for sure is that God healed whatever Paul’s issue was.

See also:

The Baseball Diamond of Healing
Objection: God Wouldn't Heal Paul’s Thorn in the Flesh
Objection: Paul First Preached at Galatia Due to a Physical Infirmity
Objection: Paul Told Timothy to Drink Wine Instead of Believing God for Healing
Objection: Paul Left Trophimus at Miletum Sick Instead of Healing Him
Objection: Paul Couldn’t Heal Himself in Galatia
Objection: We Know That God Did Not Heal Paul, Because He Said That He Bore Marks in His Body (Galatians 6:17)
Objection: Since God Allows Persecution, Which Can CAUSE Sickness, He Allows Sickness