Galatians 4:12-14

Brethren, I urge you to become like me, for I became like you. You have not injured me at all.

Paul turns from "spanking" them to "embracing" them as a father.

13 You know that because of physical infirmity I preached the gospel to you at the first.

Some believe this is a reference to Paul's "thorn in the flesh."

We do not know what this "thorn" was. Several theories are set out. All of them are just that - theories.

14 And my trial which was in my flesh you did not despise or reject, but you received me as an angel of God, even as Christ Jesus.

Angel = messenger. We think of wings, halo and white robe.

Paul brought them the message of salvation. He was an angel.