Question:

Who were the books of the new Testament written by and what was the
relationship of these authors to Jesus?

Answer:

In some cases, it is hard to prove who wrote which books. Many of the
letters of Paul were “signed” by him, making it fairly certain, but even
this is not proof. Some of the letters have a traditional author which
has been believed since the very early church. Some of those claims are
probably pretty solid, while others are questionable. You will have to do
your own research for details of the arguments on authorship for
individual books. Most any commentary will supply the details. Below is
a list of the traditionally accepted authors of the New Testament Books:

Matthew the apostle Matthew
Mark John Mark, friend of Peter, companion of Paul on his first
missionary journey.
Luke Luke, doctor, amateur historian and traveling companion
with Paul.
John The apostle John
Acts Luke, the author of Luke
Romans-Philemon the apostle Paul
Hebrews unknown
James James, the brother of Jesus
1,2 Peter the apostle Peter
1,2,3 John the apostle John
Jude Jude, the brother of Jesus
Revelation the apostle John.

The author of Hebrews is the most hotly debated. Bottom line, we do not
know the author and anyone who is confident they know who the author is is
not to be trusted.

The authorship of 1,2,3 John, Jude, and to some extent Revelation are
fairly controversial

There is some controversy about the authorship of the other books, but
most conservative scholars accept that the author identified above is
likely the actual writer of the books.

All the authors mentioned above knew Jesus personally, with the exception
of Luke. Luke was a gentile who came into contact with Christianity
through the missionary work of Paul.

John Oakes