What does John 5:4 mean?

John 5:4 is not typically found in most modern translations. Those which do include it often note that it is not found in the older or more reliable manuscripts. The disputed text indicates that an angel would agitate the water of the pool, and the first invalid into the water after that would be healed. This has raised some theological questions, such as why God would make healing into a contest, or create such a routine expression of miraculous power.

According to manuscript evidence, the most likely answer is that these words were not part of the original text of the Gospel of John. They might have been written into a margin, as a note, or a traditional explanation of the pool. At some point, the note might have been inadvertently copied into the main body and been absorbed as part of the text itself.

Ultimately, this is a better example of biblical reliability than of biblical weakness. Verses such as John 5:4 represent the most extreme version of "variants" found in scriptural manuscripts. The text itself, accepted or not, has no real bearing on any doctrine, belief, or other meaningful facts of the faith. In other words, it's simply not that important. The Bible is an amazingly well-preserved and well-documented work.