How do we know that the Gospel of John is true?

The authenticity of the Gospel of John rests significantly on the personal testimony of John the Apostle, who writes in John 21:24 that he is a witness to the events he recounts. John emphasizes the certainty of his testimony, stating, 'We know that his testimony is true.' This claim is further validated through the historical accounts of Jesus' life, death, and resurrection, along with the witness of other apostles, each of whom affirmed the truth of the Gospel. Additionally, the transformative impact of the Gospel on believers throughout history serves as a testament to its truth, as it continues to bear fruit in the lives of those who embrace its message of grace and redemption.