When Jesus was pierced, why did blood and water come out of His side?

WHAT DOES THE BIBLE SAY?

On the day Jesus died, in preparation for the Sabbath, the Jewish leaders requested that the victims’ legs be broken to hasten their deaths. While the soldiers broke the legs of those crucified alongside Jesus (John 19:31–32), they saw that Jesus was already dead (John 19:33). To confirm this, they pierced His side with a spear, resulting in John’s report of blood and water flowing out (John 19:34). John emphasized that he saw this himself and that it fulfilled Scripture (John 19:35–37). The prophetic context includes the command that the Passover lamb’s bones must not be broken, which John applied to Jesus (Exodus 12:46; John 19:36; Psalm 34:20). He also connected the piercing to the prophecy that the people would look on the one who was pierced (Zechariah 12:10; John 19:37).

In crucifixion, death occurred through either hypovolemic shock, a rapid and sustained increase in heart rate due to blood loss, or asphyxiation. Any of these can cause fluid to build up around the lungs and heart. Piercing the heart would release the clear fluid mixed with blood. This matched John’s report (John 19:34).

FROM THE OLD TESTAMENT

• While this question is answered in the New Testament, the Old Testament provides some background in anticipation of Jesus’ death.
• The first instance is in the Passover story. In that historical account, on the night before the Israelites were freed from slavery, God came to kill the first-born of everyone in Egypt. However, He provided a way for the Israelites to escape by telling them to kill a perfect lamb, saying “you shall not break any of its bones” (Exodus 12:46). The blood of that lamb was to be placed on the doorposts so that God would pass over those houses. John would connect this to when Jesus died.
• In addition to Passover, there was also an Old Testament promise that the Messiah would be pierced. God said, “I will pour out on the house of David and the inhabitants of Jerusalem a spirit of grace and pleas for mercy, so that, when they look on me, on him whom they have pierced, they shall mourn for him” (Zechariah 12:10). John also connects Jesus’ death to this prophecy.

FROM THE NEW TESTAMENT

• John provided a unique eyewitness account of the end of the crucifixion. He wrote, “But one of the soldiers pierced his side with a spear, and at once there came out blood and water” (John 19:34). He added that “he who saw it has borne witness,” emphasizing that John personally witnessed the event (John 19:35).
• The context helps explain why the soldier did this. Because of the approaching Sabbath, the authorities requested that the victims’ legs be broken to speed death. However, “when they came to Jesus and saw that he was already dead, they did not break his legs” (John 19:31–33). Instead, they thrust a spear into His side to confirm His death (John 19:34).
• Based on what is known about crucifixion, death usually occurred due to hypovolemic shock from blood loss or asphyxiation as the victim lost the strength to lift themselves to breathe. Both conditions can cause fluid to build up in the chest, either in the sac surrounding the heart (pericardial effusion) or around the lungs (pleural effusion).
• A spear pushed under the ribs could enter the chest cavity and rupture these fluid-filled spaces along with blood vessels, releasing a clear, watery fluid along with blood. John’s simple description aligns with what one would expect from this type of death and shows that Jesus was truly dead.
• However, John also realized that there was more to this than simply confirming Jesus' death. Instead, the way Jesus died confirmed that He was the one Scripture had prophesied. He said, “These things took place that the Scripture might be fulfilled: ‘Not one of his bones will be broken.’ And again another Scripture says, ‘They will look on him whom they have pierced’” (John 19:36–37). Jesus’ unbroken bones identified Him as the true Passover Lamb (Exodus 12:46), and being pierced connected His suffering to the promised figure who would be seen and mourned (Zechariah 12:10).

IMPLICATIONS FOR TODAY

Jesus’ death was a real event, witnessed and described by John, one of His closest followers. The reason He died is significant: all sin requires death (Romans 6:23a). Because of this, Jesus couldn’t just suffer—He had to die. His sacrifice was necessary to pay the price for our sin.

But incredibly, Jesus didn’t stay dead. Three days later, He rose again—conquering death itself—and is now alive in heaven. His resurrection is proof that His death completely satisfied the punishment for sin. It shows that His sacrifice was enough to bring us forgiveness and new life.

Because of what Jesus did, He made a way for you to be saved. If you turn from your sins and trust in what Jesus has already done, God promises to consider Jesus’s death as the payment for your sins. There’s no reason to carry the burden of guilt alone—Jesus has paid it all.

So, we implore you today: receive this gift of salvation! Come to Jesus with an open heart and trust in Him. He’s ready to give you a new, eternal life.

UNDERSTAND

• The blood and water coming out of His side proved that Jesus truly died.
• Blood and water when Jesus was pierced fulfilled prophecies about the unbroken bones and the pierced one.
• These fulfilled prophecies revealed Jesus as the true Passover Lamb who died to save sinners.

REFLECT

• How does knowing that blood and water flowed from Jesus’s side deepen your understanding of the reality of His death?
• How does Jesus being the true Passover Lamb affect how you view His sacrifice for your sins?
• How does the fulfillment of prophecy in Jesus’s death strengthen your trust in the truth of Scripture?

ENGAGE

• What is the significance of John emphasizing that he personally witnessed blood and water coming from Jesus’s side?
• How do the Old Testament connections to the Passover lamb and the pierced Messiah reveal God’s plan of salvation?
• How can understanding the medical and prophetic details of Jesus’s death help us share the gospel more clearly with others?