Why do you think there are multiple books of same name?

For instance, there is John, John 1, John 2 and, John 3.
There is Corinthians 1 and 2 consecutively, Peter, Etc...

Why not all be together?

I am curious what people here think?

in the case of the NT, these are each individual letters (("epistles")) written at different times. for example in 2 Corinthians, we see that the congregation in Corinth had taken steps to address some of the things Paul advised them about earlier in 1 Corinthians.

since they are separate, individual manuscripts written some time apart from each other, they are organized as such in our Bibles. they begin with greetings and end with fond farewells, and it would be a little awkward to read both letters as though they are all one letter - people would be asking annoying questions like, why would he be greeting them all over again in the middle of a letter? - and we'd have to explain that even tho we are well aware that they are two distinct letters we put them together.

Adding to Posthuman's post, the OT books of the same name (1 Samuel and 2 Samuel, etc.) are actually considered single books in the Jewish versions of the Scripture. The books are divided for convenience, but they are continuous historical narratives.

TM: " Why not all be together..."For instance, there is John, John 1, John 2 and, John 3."
Of course, the Gospel is a different literary genre than an epistie. The separation of 1-3 John acknowledges that they were originally separate episles. Their author "John the Elder" (2 John 1: 3 John 1) is to be distinguished from the Apostle John, the son of Zebedee. Papias (60-130 AD) derives information about Gospel authorship directly from "John the Elder, who survives until Papias's day, in contrast to the Apostle John, whom Papias says was martyred just as his brother James was.

TM: "There is Corinthians 1 and 2 consecutively, Peter, Etc..."

I will simply summarize the scholarly consensus. Around 85 AD, Paul's epistles were collective and edited into 7 letters--an example later followed by the Letters to the 7 Churches in Revelation 2-3. 2 Corinthians and Philippians each represent 2 letters spliced together to create the number 7 epistles. Not all the Pauline epistles were currently available to the collector. Thick scholarly books have been written to explain how scholars know this happened and what the telltale signs of editorial seams are in 2 Corinthians and Philippians. The topic is usually called "the integrity of the Pauline epistles," meaning not their authenticity, bur rather whether they were originally one or more letters.

Papias calls 'John the elder' an apostle, eyewitness and disciple of Christ.

Ignatius affirms this.

Eusebius, 100+ years later, denies it.

Because logic dictates that if you wrote a letter today, then another letter a month from now, they cannot be the same letter.

[posthuman: "Papias calls 'John the elder' an apostle, eyewitness and disciple of Christ."

Papias distinguishes John the Elder from John the son of Zebedee. Papias does label John the LElder " a disciple," but he was not 1 of the 12. So Papias distinguishes what a dead John the son of Zebedee used to say from what a still living John the Elder is currently saying.

posthuman: "Ignatius affirms this."

Nope!

Eusebius, 100+ years later, denies it."

Irenaeus does explicitly identify John the Apostle as the disciple who leaned on Jesus breast and as the author of the Gospel of John.
And as a disciple of Polycarp who was a disciple of John the Apostle, Irenaeus has a pretty good pedigree to accurately identify John the Apostle as the author of the Gospel of John.

And the Muratorian Fragment also explicitly identifies John the Apostle as the author of the fourth Gospel

When you look at the internal and external evidence together, there is no other potential candidate who comes close to John the Apostle.

This ^^^^^^^^^^^^^^^^^^^^^^^^^

Sipsey: "Irenaeus does explicitly identify John the Apostle as the disciple who leaned on Jesus breast and as the author of the Gospel of John. And as a disciple of Polycarp who was a disciple of John the Apostle, Irenaeus has a pretty good pedigree to accurately identify John the Apostle as the author of the Gospel of John."

Papias (60-130 AD) is our earliest source for who wrote our Gospels and he distinguishes the apostle John the son of Zebedee from John the Elder and makes it clear that John the son of Zebedee had been martyred like his brother James, but that John the Elder is alive and still bearing witness. The Johannine epistles are written by the same author as the Fourth Gospel and this author identifies himself as John the Elder, not John the son of Zebedee (2 John 1; 3 John 1). John the Elder is also a disciple, but not one of the 12. The John that Polycarp heard is also likely this John the Elder.

You may wish to believe the reference of elder and run with it as others, but the whole case for “another” John is very weak. I am not blind as to the history of our book, but neither am I blind to the conspiracy to tilt its credibility.

Do you also agree with Paias as to his chiliast views?

First, John the Elder, though not one of the 12, was a "disciple" and therefore had personal contact with Jesus.
Second, in any case, The "we" in 1:1-3 need imply no more than that this epistles stems from the community of the eyewitnesses.

Sipsey: "You may wish to believe the reference of elder and run with it as others, but the whole case for “another” John is very weak. I am not blind as to the history of our book, but neither am I blind to the conspiracy to tilt its credibility."

On the contrary, rejection of authorship by John the son of Zebedee is now the virtually unanimous scholarly consensus. True, conservative NT scholar, Raymond Brown, identified the Beloved Disciple as John the son of Zebedee in his massive 2 volume commentary on John. But even he later recants that identification in a later book on the Fourth Gospel. For example, the Beloved Disciple is always distinguished from named disciples in the same Johannine context. So in John 21:1-2 the Beloved Disciple is distinguished from the sons of Zebedee and is therefore to be identified as 1 of the 2 unnamed disciples.

Modern Bible scholars have good reason to reject the testimony of Church Fathers from the end of the 2nd century an later.
(1) They live beyond the time of surviving members of the 12. Papias is from the apostolic age and his witness that the son of Zebedee had been martyred should be accepted and finds confirmation in Mark 10:34, 38-39). But John the Elder, "a disciple of Jesus," is still alive and in circulation in Papias's day.

(2) The Church Fathers are famous for their conflation errors. Philip the Apostle is conflated with Philip the Evangelist in Acts. Mary Magdalene is conflated with both Martha's sister Mary and the prostitute of Luke 7:36-50, who also anoints Jesus with expensive perfume like Martha's sister. Thus, the myth of Mary Magdalene the prostitute is created! John the son of Zebedee, John the Elder, and John the Seer of Revelation are 3 different men who are conflated into one. No modern scholar now believes that John the son of Zebedee wrote the Book of Revelation.