Expositor's Bible Commentary Commentary John 5:4

"[for an angel of the Lord went down at certain seasons into the pool, and troubled the water: whosoever then first after the troubling of the waters stepped in was made whole, with whatsoever disease he was holden.]" — John 5:4 (ASV)

Excavations have located this pool in the northwest corner of old Jerusalem. It was surrounded by a colonnade on all four sides and down the middle of the pool. People gathered at the water’s edge, hoping to be cured of their ailments, when the water was agitated. The explanation of the moving of the water (v.4; see NIV note) was probably added to the text of John later.