The Old Testament writers were all prophets. There were three
categories of prophets.
Moses was a unique prophet. He wrote the first five books of the
Old Testament, called the TORAH. He was unique because he had
both the gift and office of prophet. Moses received all his information
by dialogue directly from God.
There were those with the office of prophet, called the NEBI'IM.
These men include Joshua, Samuel (Judges and Samuel), Nathan and
Gad (parts of Samuel, Kings, Chronicles), Isaiah, Jeremiah, Ezekiel,
and the twelve minor prophets: Hosea, Habakkuk, Zechariah, Malachi,
Amos, Joel, Obadiah, Jonah, Micah, Nahum, Zephaniah, and Haggai.
There were those with the gift, but not the office, of prophecy
(they did something else by profession). They wrote the KETHUBIM,
which means the writings. They include David, Solomon, Job, Daniel,
Ezra, Nehemiah, Esther, and Chronicles.
Every extant book of an acknowledged messenger of the Lord who
was commissioned by God to make known His will was accepted immediately
as the Word of God in the formation of the Old Testament Canon.
The formation of the Old Testament was closed in the reign of
Artaxerxes Longimanus I (465-425 B.C.). Ezra came to Jerusalem
in the seventh year of Artaxerxes I; Nehemiah came in the twentieth
year of his reign. These were the two last writers of the Old
Testament.
The New Testament was written primarily in Koine (common) Greek.
Prior to Koine, there were three major branches of Greek language
in classical times: Aeolic, Doric, and Ionic (Attic). The conquest
of Alexander led to the formation of a common Greek language,
Koine, which became the lingua franca from around B.C. 300 until
500 A.D.
New Testament writers were those with the gift of apostleship
or who were closely associated with an apostle (Mark with Peter;
Luke with Paul).
Only Luke and Paul break out in Attic Greek at times, showing
their higher classical education. Most of the New Testament is
in Koine Greek so that the Word of God could be understood by
the common man.
Biblical Descriptions for the Canon of Scripture.
Heb. 4:12, "The Word of God."
1 Cor. 2:16, "The mind of Christ."
Heb. 3:7, "The voice of the Spirit."
Jer. 1:9, "Behold, I have put My words in your mouth."
Mark 12:36; Psalm 51:4; Heb. 10:35-36.
Acts 28:28, "The Holy Spirit rightfully spoke to Isaiah..."
Psalm 138:2, "For You have exalted above all things Your
person and Your doctrine." God has placed the highest possible
value on the Scripture.
Rom 3:3, "You have become justified in your sayings ..."