Appropriately, there are four Johns associated with the Fourth Gospel: John, the Baptist; Saint John, the son of Zebedee (one of the 12 apostles); John, "the beloved disciple"; and John, the elder (or presbyter).
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Even in 2008, some people still believe that Saint John, the apostle, the son of Zebedee, wrote the Fourth Gospel. This belief flies in face of all the evidence in the Gospel itself where the author clearly identifies himself as "John, the beloved disciple."
Most people stop at this point and simply assume that John, the apostle, the son of Zebedee, is the same John as "the beloved disciple", despite the fact that the author further identifies himself as a person "well-known to the High Priest."
This description hardly fits an illiterate, Galilean fisherman. It's like saying that an uneducated youth who'd worked all his life on his father's fishing smack in the lower reaches of the Mississippi in an area where strangers were not welcome, was not only acquainted with the Archbishop of Boston but was such a frequent visitor to his palace in that distant city that the gatekeeper instantly recognized him! Surely a ridiculous assumption! There's no way in the world that the "beloved disciple" can be the same person as Saint John, the apostle, the son of Zebedee.
Consider these further facts: 1. John's Gospel is written in Greek. John Zebedee could not even write his native Aramaic, let alone Greek! All right, perhaps he dictated the Gospel?
2. Doesn't it strike you as odd that John never mentions James? Not even once in his entire New Testament output. Not in his Gospel, not in his Letters, not in Revelation. Yet the synoptic Gospels tell us that the brothers. James and John Zebedee, were absolutely inseparable. They went everywhere together, did everything together, and were always talking loudly to each other. Okay, perhaps after James was martyred, John was simply trying hard to live without him. Perhaps it became just too painful to call him to mind, even after a lapse of 30 or 40 years?
3. What was the most marvelous event to which John and James were eye-witnesses in Jesus' lifetime? Answer: the Transfiguration. Yet this incident isn't mentioned in John's writings at all. Why not? Jesus had forbidden the brothers to tell anyone about it until "the Son of Man has risen from the dead." (Mark 9:9). But Jesus had long risen by the time John produced his Gospel around the year 100 A.D. But perhaps he thought it was now old news and not worth repeating?
4. Both Mark and Matthew plainly imply that John and Peter were friends. Luke is more specific. He uses two words to describe their relationship. First, in 5:7, he says they were "partners". Then in 5:10, he states specifically they were "friends" or companions. (The Greek word is "koinonos"). Well, some friend John turned out to be! If you read the original Greek (or accurate translations like that by J. B. Phillips), you will be surprised at the overt hostility John often displays towards Peter. John obviously saw Peter as a rival for Jesus' affections and he never loses an opportunity to cut Peter down to size. Needless to say, most translations go out of their way to disguise this jealousy, but it's there nonetheless (plainly transcribed by Canon Phillips and pretty obvious from a close reading of the New American Bible). Well, perhaps John Zebedee changed his once-friendly attitude towards Peter? Maybe he wasn't so saintly after all? Maybe he became quite sour in his old age?
5. I could go on, and keep asking obvious questions like "Where's James?" But I'll make this point the clincher. It's John 19: 26,27: One of the most moving scenes in the New Testament. Jesus is dying on the cross. John "stood near with His mother." Jesus saw them standing together and He said, "Look, mother, here is your son!" And He then turned to John and said, "Look, John, here is your mother!" And John writes: "From that time forward, I took her into my own home and took care of her." Would Jesus entrust his mother to a "loudmouth" (Jesus' own description), quarrelsome Galilean fisherman? (Remember, at this stage the disciples had not yet received the Holy Spirit). And what fisherman would have a home of his own? John Zebedee would have been obliged to take Mary back to his father's shack in Galilee. And how would he spare time to take care of her? According to Luke (Acts 1: 2-5), the "chosen apostles" were "commanded" by Jesus "not to leave Jerusalem, but to wait for the Father's promised gift", namely "the Holy Spirit." After which Peter and John, "uneducated men with no qualifications" (Acts 4:13), spread the Good News in Jerusalem: "The apostles all used to meet together in Solomon's Colonnade." (Acts 5:12).
Afterword from John's Gospel:
The sum total of the message we have heard from Jesus and now record for you, is simply this: God is Light and there is no trace of darkness in Him at all. If we claim to have fellowship with Him yet continue to walk in darkness, we are lying, for we are not walking in the way of truth at all.
On the other hand, if we walk in the Light as He is in the Light, we not only have fellowship with Him, but with one another. And the blood of His Son, Jesus, cleanses us from all sin.
If we say we are sinless and don't need cleansing, we deceive ourselves and truth does not reside in us. If we say we have never sinned, we make Him a liar and His word is not in us.
On the other hand, if we confess out sins to Him, He will forgive all our offenses and cleanse us from all unrighteousness. Fore He is not only faithful, but righteousness itself.