For an angel went down at a certain season into the pool, and troubled the water: whosoever then first after the troubling of the water stepped in was made whole of whatsoever disease he had.
John 5:4

Was the angel a messenger sent from the Temple or one from Heaven? Most Christians believe a Heavenly Angel, but I'm not certain. This verse is missing from some manuscripts and the ESV leaves it out. I suspect that the ESV is right on this and that it was just a superstition.