This lectionary passage is one of the longest I ever recall reading. It encompasses John’s entire recounting of the night and day of Jesus’ death–from his betrayal by Judas and arrest by the authorities, through Peter’s denial of him, his trials before both the high priest and Pilate, the crucifixion itself, and finally his burial. While liturgically it certainly makes sense to consider this entire series of events as a whole, it is quite a lot of text to cover in one short devotional or commentary. So I will focus instead on one small aspect of this passage–one which could arguably be said to be the climax of the entire story: the water and blood flowing from Jesus’ side on the cross (19:34). This event is also the climax of the water imagery in the Gospel of John, which I’ve written about in other commentaries.
John is the only Gospel which relates the incident of the water and blood from Jesus’ side, which leads to the question of why he thought it so important. There have been many attempts through the centuries to posit both a practical and physical explanation for what happened here. For example, some have suggested that when the soldier thrust the lance into Jesus’ side he aimed for the heart, with the purpose of mortally wounding him to ensure that he would actually die quickly. However, the soldiers have already observed that he is dead in v. 33, which is why they don’t break his legs. So that would seem to negate this theory. A more likely explanation is that the soldier intended to simply prod Jesus to detect signs of movement; in the process he became overzealous and actually pierced the skin. There is evidence that this might have been a common practice among Roman execution squads to verify a person’s death, and the verb nysso can mean “to prod” as well as “to plunge or pierce.”
For the last 200 years medical professionals have attempted to find a physical explanation for how blood and water could have flowed out of Jesus’ body after death, as this is not a normal occurrence. However, this approach has been justly criticized for attempting to extract physical details of Jesus’ torture and death from a narrative that does not provide such material. The description of Jesus’ crucifixion is extraordinarily terse in both John and the Synoptics, consisting of only a few words–no more than a dispassionate statement of fact (Matt 27:35; Mk 15:24; Lk 23:33; Jn 19:23). A little more can be ascertained from what we know about crucifixion as practiced by the Romans, but even there the data is somewhat scanty. Most importantly, though, this approach is not helpful because the narratives of Jesus’ crucifixion are written for primarily theological, not physiological, reasons; one cannot expect to draw conclusions about physical matters because the Gospel writers themselves were not particularly concerned with them.Their focus was not on how Jesus died so much as why he died and what that death meant.
This is nowhere made clearer than in this moment on the cross. This event of the blood and water is so extraordinary, so unbelievable, that the narrator highlights it by adding: “He who saw this has testified so that you also may believe. His testimony is true, and he knows that he tells the truth” (19:35). In other words, John interprets these events as incredibly unusual–even miraculous. This would seem, then, to negate the need for a physical explanation for the blood and water, because it clearly is beyond the range of human comprehension.
So what was the author’s theological purpose for including the detail of the blood and water? There are several possible answers but perhaps the most natural is to see blood and water as indicating that Jesus has fulfilled the requirements of the Passover sacrifice. The Gospel of John makes very intentional links between Jesus’ death and the sacrifice of the Passover lamb; indeed, the entire passion narrative is molded to emphasize this role, especially when compared with the Synoptic versions. This is the explanation for the shifting of the time of Jesus’ death from the day of the Passover itself to the day before the Passover, the day of Preparation when the lambs were slaughtered (cf. Jn 13:1; cmpr Mt 26:17; Mk 14:12; Lk 22:7). It is also the reason behind several minor tweaks John makes to the Passion narrative including the use of a hyssop branch–the traditional vehicle for transferring sacrificial blood to the one being cleansed–by the soldiers to administer the wine to Jesus (19:29), and the inclusion of the Scripture quotations after the piercing of his side (19:36-37).
Water, of course, also has the ability to cleanse from impurities in Jewish law and practice.And purification issues have already occupied a place in John’s Passion narrative. Concern for ritual purity seems to underlie the Jewish leaders’ insistence that Jesus’ body be removed from the cross before the sun set (19:31), for example. Plus, connections between water, purification, and Jesus’ death were established early in the Gospel. John’s practice of baptizing with water directed people to the Lamb of God who would take away the sin of the (John 1:29-34). The sign at Cana foreshadowed the ‘hour’ of Jesus’ passion, when purification would be accomplished through the revelation of his glory (2:1-11). Jesus washed his disciples’ feet in anticipation of the cleansing that he would provide through his death (13:1-11).
Given these connections, it is appropriate to see the water flowing from Jesus’ side as a way of conveying the purifying aspect of his death. To some, the body of Jesus was a source of defilement, but in the eyes of the evangelist, the crucified Christ is a source of cleansing from sin, one of many Johannine ironies. Therefore, seeing the blood and the water in 19:34 as representative of the cleansing from sin that comes to all through Christ’s death is certainly not inappropriate, either within the context of Jewish theology or the previous understandings in the Gospel of John.
However, this is not the only way to understand these symbols. Indeed the tradition of reading the water and blood as representative of the sacraments of Baptism and Eucharist is related to their ability to provide purification. After all, baptism is connected to the idea of cleansing from sin or impurity in much of Christian thought, and is certainly the primary understanding of baptism in the Synoptics.However, in the Fourth Gospel baptism serves a revelatory function (1:31; 3:27-35). In John baptism is never connected directly to the idea of the forgiveness of sins or cleansing from impurity, nor is water. Therefore, although later Christian thought may see the water in 19:34 as representative of baptism, this does not seem to be a natural interpretation in the Johannine context. However, seeing the water from the side of Jesus as revelatory in some way of his identity, a function we have seen water serve elsewhere in the Gospel (2:11; 4:10-26; 6:19-20; 7:37-39) is a valid interpretation. Indeed, this is where the connection between water and Spirit in the Gospel reaches its climax and its ultimate purpose.
In John 7 Jesus stood up at the Feast of Tabernacles, on the day of the water festival which was part of the celebrations, and declared that rivers of living water would flow from him (and/or from the believer–the text is not quite clear, vv. 37-38). The narrator breaks in to tell us that the water he speaks of represents the Spirit, which he implies will not be given until Jesus is glorified (v. 39). Given this statement, water flowing from the side of Jesus at his death is an especially evocative image. Within the context of the Gospel, it is clear that this is intended to be the climax of the water motif: the living water which Jesus alone can give (4:10-14), which will flow out of him and through all those who believe (7:37-38), which represents the Spirit (7:39), is now literally released at the moment of Jesus’ death. The imagery could hardly be any clearer: Jesus’ death provides the Spirit.
The image of water from Jesus’ side also has strong connections to previous Jewish metaphors concerning the coming of the new eschatological age foretold by the prophets, which Jesus’ ministry has been inaugurating all throughout the Gospel. One of the most natural connections the Jewish audience might make between both Jesus’ statement in 7:37-39 and the flow of water from his side in 19:34 is with the vision of the end times in Ezekiel 47:1-12. Here the prophet is shown a river flowing from the temple in Jerusalem which brings healing to the dry, dead landscape and makes salty waters fresh. Earlier in the Gospel, the narrator made an explicit connection between Jesus’ body and the Jerusalem temple (2:21). The flow of water from Jesus, then, is an indication that the new age of blessing foretold by the prophets was beginning as a result of Jesus’ ministry and death. This new age was not something relegated to the distant future, as it was to the people of Ezekiel’s day, but was here now.
A similar image is found in Zechariah 14:8 which pictures living waters flowing in two streams out of Jerusalem at the end of the age. However, the parallels extend far beyond this single verse. Indeed, all of Zechariah chapter 14 seems to have particular resonance with Jesus’ statement in 7:37-38 and its surrounding context. Zechariah speaks of the “day of the Lord” when the nations will rally against Jerusalem and the Lord will come in power to win victory and reign supreme. The key elements in the prophecy are these: Jerusalem will be occupied by alien forces (14:1-2); the Lord will appear and fight on Israel’s behalf (14:3); he will “stand upon the Mount of Olives, east of Jerusalem” and provide an avenue of escape for His people (14:4-7). On that day living water will flow out from Jerusalem; the Lord will be King over the whole earth (14:8-9a) and the surviving nations will celebrate Tabernacles in Jerusalem (14:16-19). Each of the crucial elements of this prophecy play a part in Jesus’ appearance at the feast of Tabernacles. At that time Jerusalem was indeed under alien occupation (as it had been for several hundred years); Christ appeared (midweek and unexpectedly) at Tabernacles to offer Himself on the behalf of the faithful; Jesus stood and promised living water and then retired to the Mount of Olives. The striking similarities between these two passages also support the idea that John is framing the water from Jesus (both metaphorical and literal) as concrete evidence that the Messianic Kingdom foretold by the prophets has now arrived in his person.
In typically Johannine fashion the author of this Gospel is not content for the symbols of water and blood in John 19 to point to just one meaning. Instead, they represent several different strands from Jewish soteriology and eschatology: water and blood as part of the sacrificial system for the atonement of sins, water as revelatory of identity, and the connection of running water with the giving of the Spirit. All of these are woven together to create one inescapable message: with the death (and eventual resurrection) of Jesus, everything has changed, the promises of the prophets have been fulfilled, and Jesus has been revealed once and for all as God himself incarnate.
 All translations are from the NIV, 2011 edition.