What does John 19:30 mean?

The "sour wine" mentioned in prior verses was either something meant to numb pain (Matthew 27:34), or simply a harsh liquid that happened to be nearby when Jesus noted His thirst (John 19:28). Either way, Jesus knew He was seconds away from death.

John presents Jesus' declaration here using the Greek word tetelestai. Archaeologists have found this word inscribed on records to indicate debts which have been paid, or obligations which have been met. That which Jesus was sent to accomplish—an atonement for sin on behalf of mankind (2 Corinthians 5:21)—is entirely and fully completed in this moment: "It is finished." No further work needs to be done, nor can it be done (Titus 3:5). There is no room for other actions, rituals, sacraments, sacrifices, or payments to accomplish salvation (1 Peter 3:18; Hebrews 10:12–14).

The fact that Jesus is said to "give up his spirit" is significant. Matthew and Luke make similar observations (Matthew 27:50; Luke 23:46). From a physical standpoint, Jesus' body has suffered fatal injury. And yet, His death is entirely an act of His own will. That included His willingness to be born into human form (John 1:14), to submit to God's will (Matthew 26:39), and to allow His own arrest and execution (Philippians 2:8). Whether literally, or as a statement of agreement, Scripture clarifies that Jesus is "giving up" His life to God the Father—it is not being stripped away from Him by force (John 10:17–18).