“But one of the soldiers pierced his side with a spear, and at once there came out blood and water.” – John 19:34

The Evidence on the Shroud

The man of the Shroud has a 1.7 inches (4.4 cm) almond-shaped wound in his right side. This wound corresponds to the double-edged blade of the Roman lance.

What John Saw: the Gospel Account

John insisted in his Gospel that he witnessed the following:

• The centurions came to break the legs of the crucified men to speed up their deaths.
• Jesus was already dead, so his legs were not broken.
• A centurion pierced the side of Jesus with a lance.
• Blood and water flowed out from this wound.

What John Saw: the Forensic Explanation

About 30 to 60 minutes after death, when the heart stops pumping, blood separates into a dense fluid of red blood cells and clear watery plasma. This happened to Jesus on the cross.

The lance penetrated approximately 3.5 inches (9 cm), reaching the right atrium or ventricle of the heart. The layer that John described as “water” was probably serous pleural and pericardial fluid that appeared to be clear and therefore looked like water to John.

Pleural Effusion

The severe beating from the scourging combined with the hard falls while carrying the heavy crossbeam caused blood and fluid to build up in Jesus’s chest cavity. Once his heart stopped beating and circulating blood, the bloody fluid that filled his chest settled into two layers: a bloody layer and a clear fluid layer.

Scientists Discovered the “Water” in 1978

The red blood on the Shroud can be seen with the naked eye, but not the “water” that John reported. This layer appeared when the STURP team photographed the Shroud with X-ray fluoroscopy.

STURP Scientists measured the ultraviolet fluorescence in the area of this bloodstain. They discerned the presence of the cellular components of blood, but also the transparent serous fluid.

This Was Post-Mortem Fluid

Forensic scientists agree: the man of the Shroud was dead at the time of the wound to his side. The presence of both blood and watery serum confirms this.

The Flow of the Fluid

• Flows vertically down the right side of the chest
• Spreads horizontally across the back

The Spear Wound

• Between the fifth and sixth ribs on the right side
• Exactly matches the shape of a lancia (Roman lance)
• Oval shaped, 1.75 inches by 0.44 inches (4.4 cm by 1.1 cm)

What John Saw: The Theological Meaning

Theologically, blood and water symbolizes the birth of the Church. Doctors of the Church commonly cite John 19:34, including Thomas Aquinas: “The piercing is an opening…the gate of life thrown open, from whence flowed the Sacraments of the Church…”

Take Away

John was an eyewitness to the piercing of the side of Jesus and he was very insistent about seeing the blood and water flow from his side. This eyewitness account was validated by the scientific study of the bloodstains on the Shroud by the STURP Team in 1978. This illustrates how the Scriptures and scientific inquiry can be mutually enlightening.