what is its structure?
It has four sections: A prologue, the "Book of Signs", the "book of glory", and a conclusion. The epilogue might not have been a part of the original text.
Gospel of John
The majority of scholars see four sections in John's gospel: a prologue (1:1–18); an account of the ministry, often called the "Book of Signs" (1:19–12:50); the account of Jesus' final night with his disciples and the passion and resurrection, sometimes called the "book of glory" (13:1–20:31); and a conclusion (20:30–31); to these is added an epilogue which most scholars believe did not form part of the original text (Chapter 21).
how many chapters does the gospel of john have 21.
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Gospel of John [SEP] Structure and content
The majority of scholars see four sections in John's gospel: a prologue (1:1–18); an account of the ministry, often called the "Book of Signs" (1:19–12:50); the account of Jesus' final night with his disciples and the passion and resurrection, sometimes called the "book of glory" (13:1–20:31); and a conclusion (20:30–31); to these is added an epilogue which most scholars believe did not form part of the original text (Chapter 21). The structure is highly schematic: there are seven "signs" culminating in the raising of Lazarus (foreshadowing the resurrection of Jesus), and seven "I am" sayings and discourses, culminating in Thomas's proclamation of the risen Jesus as "my Lord and my God" (the same title, "dominus et deus", claimed by the Emperor Domitian, an indication of the date of composition).