It is always helpful when a NT writer clearly states his reason for writing. John does that for us. “And truly Jesus did many other signs in the presence of His disciples, which are not written in this book; but these are written that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in His name” (20:30-31). Because we have an interest in the salvation of souls, we should have an interest in the gospel of John because John’s message will bring people to Jesus. Some have taken the Gospel of John by itself, giving this book alone to an unbeliever, and then that person will come to have faith in the Messiah. The Gospel of John is easy to read; it is exciting in its movements; it is convincing in its logic. There is even within the book itself a model, an example from the life of Jesus, that will help us in teaching others. Read chapter four and see how Jesus taught the woman at the well. That pattern can help us in teaching others.
The Gospel of John is about faith. John the Baptist, the forerunner of Jesus, had faith in the Messiah; the Baptizer in turn passed his faith on to his followers—that is, he took a back seat to Jesus, decreasing as Jesus increased, and his disciples became disciples of Jesus; in fact, some became apostles. Read John one and see how one person would invite another person to consider who Jesus was. The Gospel of John is designed to provoke a response in the hearts of those who encounter Jesus. Not all came to have faith in Jesus; but there was adequate evidence presented to convince the fair-minded that Jesus was who He claimed to be—the divine Son of God.
Even a casual reading of John will show that is different from the Synoptics. While there is a decided interest in reaching out to the lost in each book, Matthew, Mark, and Luke concentrate on incidents in the life of Jesus; their narratives tell His story. Yet, John’s story about Jesus revolves largely around seven miracles that highlight Jesus’ purpose for coming into the world. For example, Jesus gave sight to the blind; the larger lesson is that Jesus gives to all who will come to Him spiritual sight in order to leave the blinding nature of sin.
Many (not all by any means) believe John wrote his books (the gospel of John, 1st, 2nd, 3rd John, and Revelation) near the end of the 1st c. This could have been anywhere from AD 80 to AD 100. Fragments of John’s gospel help us understand that it was circulating as early as AD 125. Writers (Irenaeus AD 185) mention John as the one whom Jesus loved (John 21:20). Add to that the mention of the isle of Patmos (Rev. 1:9), the place of John’s exile, and you have factors that can lead to the conclusion that John’s writings came later in the 1st c. John 12:48 says: “He who rejects Me, and does not receive My words, has that which judges him–the word that I have spoken will judge him in the last day.” Let us receive Christ’s words now; we will face them in the judgment. – Randy Harshbarger