What is the meaning of Acts 12:9?

* The two F.O.G. Bibles & Commentary below are currently a work in progress.

So Peter followed him out, but he was unaware that what the angel was doing was real. He thought he was only seeing a vision.

Berean Standard Bible (BSB)

And he went out and followed him. He didn’t know that what was being done by the angel was real, but thought he saw a vision.

World English Bible (WEB)

And{G2532} he went out{G1831}{(G5631)}, and followed{G190}{(G5707)} him{G846}; and{G2532} wist{G1492}{(G5715)} not{G3756} that{G3754} it was{G2076}{(G5748)} true{G227} which{G3588} was done{G1096}{(G5740)} by{G1223} the angel{G32}; but{G1161} thought{G1380}{(G5707)} he saw{G991}{(G5721)} a vision{G3705}.

Strong's King James

(9) He went out following and he didn't know that what's being done by the messenger-angel was real but thought he was seeing a vision.

The F.O.G*

[9] Peter followed the angel out, but everything seemed so surreal that he thought he was seeing a vision. Sometimes God's intervention seems too good to be true.

The F.O.G Paraphrase

and having gone forth, he was following him, and he knew not that it is true that which is done through the messenger, and was thinking he saw a vision,

Young's Literal Translation