Who wrote many of the letters in the Bible?

A:

Thirteen letters, or epistles, are attributed to St Paul, while seven epistles have traditionally been attributed to four of the twelve disciples of Jesus. However, the consensus of scholars is that of the epistles attributed to Paul, only Romans, 1 Corinthians, 2 Corinthians, Philemon, Galatians, Philippians and 1 Thessalonians are genuine, with the remainder written in Paul's name after his death. A.Q. Morton goes further, having carried out a computer analysis of the epistles attributed to Paul and found that only Romans, 1 Corinthians, 2 Corinthians and Philemon contain exactly the same writing style as Galatians. Moreover, not one of the epistles attributed to James, John, Jude and Peter can safely be attributed to the named apostles.

Whether Paul really wrote 7 or only 5 letters in the Bible, his contribution is considerable.