Instead, one of the soldiers pierced His side with a spear, and immediately blood and water flowed out. — John 19:34

John records the detail with clinical precision: the soldier pierced Jesus' side, and blood and water flowed out. This wasn't just a biological observation—it was a theological sign. The blood for atonement, the water for cleansing—both flowing from the same wounded savior. This is the fountain zechariah spoke of, opened for sin and uncleanness.