The verse John 20:31 in the King James Version of the Bible reads: "But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name."

This verse is found at the end of the gospel of John, and it serves as a conclusion to the purpose of the book. Throughout the gospel, John has been recounting the life, teachings, and miracles of Jesus Christ, with the intention of leading his readers to belief in Jesus as the Son of God and the source of eternal life.

The overarching theme of the gospel of John is that of belief. Throughout the book, John emphasizes the importance of believing in Jesus as the Messiah and Son of God. The verse in question underscores this theme, as it explicitly states that the purpose of the gospel is to lead people to belief in Jesus as the Christ. By believing in him, eternal life is obtained through his name.

The context of this verse is important for understanding its significance. John wrote his gospel with a clear purpose in mind: to demonstrate the deity of Jesus Christ and to encourage belief in him. Throughout the gospel, John presents Jesus as the Word made flesh, the light of the world, the bread of life, and the resurrection and the life. He records Jesus' miracles and teachings, all of which point to his divinity and the offer of eternal life to those who believe in him.

In the immediate context of this verse, John is addressing his readers and making it clear that the accounts of Jesus' life, death, and resurrection have been written for the very purpose of leading people to faith in Jesus. The emphasis on "believing" in this verse ties back to themes found throughout the gospel, particularly in John 3:16, which states, "For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life."

The symbolism in this verse is quite profound. The act of writing and the purpose behind it is significant. John is essentially saying that the gospel is a written testimony to the truth of who Jesus is and what he came to do. The act of believing in Jesus as the Christ is seen as the key to obtaining eternal life. Through his name, believers have access to life, both in the present and for all eternity.

The name of Jesus holds great significance in the Bible. In the book of Acts, Peter declares, "Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved" (Acts 4:12). The name of Jesus represents his identity and authority as the Son of God and Savior of the world. Believing in his name is synonymous with trusting in his person and work, and this belief is the means through which eternal life is received.

In summary, John 20:31 encapsulates the main message of the gospel of John, which is to lead people to belief in Jesus as the Christ, the Son of God, and to receive eternal life through faith in his name. The verse serves as a powerful reminder of the centrality of belief in the Christian faith and the significance of Jesus as the source of life. It also underscores the purpose and intent behind the gospel of John, which is to bring people to a saving knowledge of Jesus Christ.