What does John 14:19 mean?

"The world," in these contexts, means the unbelieving and fallen human condition. Jesus promised the Holy Spirit would come (John 14:16), but noted that unbelievers would neither see nor know Him (John 14:17). Here again He notes that this is the end of His earthly presence, in a form visible even to those who do not believe (John 12:44–46). The disciples, on the other hand, will see Jesus again, and soon (John 16:16; 20:19).

Scripture often ties the life of a believer to the life of Christ—we live because He lives (1 Corinthians 15:21). Those who have faith in Christ are said to have passed from death to life (John 5:24; 1 John 3:14), exclusively because of the death and resurrection of Jesus (Romans 5:21; 6:8; John 14:6). This promise from Christ is the ultimate answer to our struggles (Romans 8:18, 28). Christians have the guarantee of redemption and restoration at the end of our earthly lives (Hebrews 11:14–16).

Christ's resurrection is the proof that those who put their faith in Him will also see victory over death (1 Corinthians 15:19–20).