What is the significance of Jesus saying, “I have overcome the world” (John 16:33)?

from the old testament

• The statement "I have overcome the world" is not found in the Old Testament.

from the new testament

• John 16:33 happened in the Upper Room Discourse (13–17) and concludes Jesus’ discussion about His impending death. It reads, “I have said these things to you, that in me you may have peace. In the world you will have tribulation. But take heart; I have overcome the world.”
• Throughout the discourse, Jesus was preparing the disciples for his death. He told them to expect the world to hate them because it hated Him (John 15:18–19), but to abide in Him (John 15:4–5), and comforted them that, though He was leaving, He would return (John 14:1–3). In this final section (John 16:25–33), Jesus spoke about the reality that His hour had come and that though His disciples say they believe (John 16:30), that very soon “you will be scattered, each to his own home, and will leave me alone” (John 16:32).
• With all this in mind, He said, “Take heart; I have overcome the world” (John 16:33b). They were to face tribulation and hardship after Jesus left, but their peace was to come from the fact that Jesus had overcome the world. The tense used here is rightly translated as if Jesus had already overcome the world even though the world was about to kill Him. Elsewhere, we learn that Jesus has victory over death after His resurrection (1 Corinthians 15:54–57), and thus His actual victory remains future.
• However, because Jesus’ death was “according to the definite plan and foreknowledge of God” (Acts 2:23), He could speak as if it were already done. Thus, He spoke as if it were already finished to reassure His disciples that what was about to happen was part of the plan and to help them not lose heart.
• Three days after this conversation, when Jesus rose from the dead, His claim of victory was fulfilled. It was there that the Son “was declared to be the Son of God in power according to the Spirit of holiness by his resurrection from the dead, Jesus Christ our Lord” (Romans 1:4).
• Many years later, John wrote that believers now overcome the world because they have Jesus. He said, “Little children, you are from God and have overcome them, for he who is in you is greater than he who is in the world” (1 John 4:4). He also said, “Everyone who has been born of God overcomes the world. And this is the victory that has overcome the world—our faith. Who is it that overcomes the world except the one who believes that Jesus is the Son of God?” (1 John 5:4–5).
• Believers overcome the world because Jesus overcame the world. This was what Jesus was saying in John 16:33. The disciples were to take heart, knowing that the victory was already secure.

implications for today

When Jesus rose from the dead, the power of sin was destroyed. Jesus not only removed death’s sting (1 Corinthians 15:54–57) and will one day destroy it completely (Revelation 21:4), but He also removed humanity’s inability to escape the ramifications of sin by paying its penalty.

Satan and sinful men intended the cross to be the end of Jesus. Instead, it was the means God was using to bring salvation to the world. Thus, when Jesus succumbed to death, it was not as a defeated foe but as a victorious conqueror.

Because of what He did, we who have trusted in Jesus for the forgiveness of sins are now more than conquerors in Christ Jesus (Romans 8:37). We, too, are no longer bound to judgment and destruction like the rest of the world. We, too, will die, but because Jesus overcame death, He now has the keys of death (Revelation 1:18) and will bring His followers back to life to live and rule with Him eternally (Revelation 22:5).

The world may be laughing at Jesus now, but Jesus has already conquered it. The last laugh will be His. It will be ours too, who are His. May we live this life fully for God, knowing that He has already won the victory and that nothing we face can overcome the One who has overcome the world.