Many readers know John 5 from translations that describe an angel descending to stir the pool and the first person entering afterward being healed. That explanation has an important textual-history qualification.
The earliest manuscripts generally do not contain the full explanatory wording traditionally printed as John 5:3b-4.
The longer reading appears to explain why sick people waited at the pool and why the disabled man later says that he has no one to put him into the water 'when the water is troubled.' His statement about the moving water is much more securely part of the text.
Possible explanations for the pool's movement include intermittent water flow or local healing belief, but John does not provide enough evidence to reconstruct the mechanism with certainty.
The textual distinction allows the narrative to be read carefully without dismissing its historical setting. The man genuinely expects an opportunity connected with the disturbed water, yet the earliest text does not itself require the evangelist to endorse the later angelic explanation.
Most importantly, Jesus heals without using the pool at all. The man's hope is fixed on reaching the water; Jesus simply commands him to rise.