Summary: John 21 describes the dynamics of discipleship
I am not a good letter writer. It seems as if I always leave something out. When I do write letters, I often have to add a P.S.
This final chapter of John's gospel seems to a postscript. The closing verses of John 20 seem to conclude the book. Then, as an apparent postscript, chapter 21 is added.
Scholars have long debated why this 21st chapter was added by John to the book.
Two answers are most often suggested. Some say, John added this chapter to clarify the nature of the church's ministry. Now that the second coming of Christ had apparently been delayed, what was the church to do? We see the answer clearly expressed in the dynamic dialogue between Jesus and Peter in verses 15-17.
Another possibility was that John added this chapter to demonstrate once and for all the reality of the resurrection. Was Jesus really raised fro the dead or was it simply an illusion? The answer to that question is clearly provided in the description of the resurrected Lord as a person who could spot a school of fish (v. 6), start a charcoal fire (v. 9), and cook and eat a meal (v. 13).
Both suggestions have merit, but I believe John's purpose was even broader than this.
The purpose of chapter 21 is to describe the dynamics of discipleship.
John ended chapter 20 with a call to discipleship. Through belief in Jesus as the Son of God, John said, we will find new life. But what would that new life be like? What would be involved in discipleship? This is the question John seeks to answer in this final chapter.
First, John tells us that when we follow Christ we will experience a fullness.
In the aftermath of the events in Jerusalem which had left the disciples confused and uncertain, they found a sense of stability by returning to the familiarity of their fishing. However, a night on the water had produced nothing but empty nets. Early in the morning hours, a man who stood on the shore suggested they put down their nets on the other side of the boat. They followed the stranger's suggestions. The stranger of course was Jesus. When they raised their nets they found them full. John says they later counted the fish and there were 153.
Scholars have offered various suggestions on the meaning of the number, 153.
Cyril of Alexandria said that the 100 represented the fullness of the Gentiles.
The 50 refers to the remnants of Israel who will be gathered into God's kingdom.
The three is a symbol of the trinity to whose glory the fullness of the Gentiles and Jews would be brought together.
Jerome said that there are 153 different kinds of fish in the sea.
Therefore, the number, in his opinion symbolized the day when all men of all nations will be gathered together in Christ.
The suggestion of Augustine was even more ingenuous. He said that 10 is the number of the commandments and thus represents the law. Seven is the number of wholeness or completion and thus represents grace. Together these numbers equal 17. When you add up all the digits from 1 to 17 the total is 153. The obvious reference then is to all who by law or by grace have been brought to Christ!