Thirteen canonical letters in the New Testament are traditionally attributed to Paul. They range from Romans, a major theological letter, to the short personal letter to Philemon.
The letters are not arranged in the order in which scholars generally think they were written. Instead, they are broadly ordered by length, with letters to churches preceding letters to individuals. Hebrews follows the Pauline collection in many traditions but is not counted among the thirteen because its authorship is uncertain and it is not formally addressed as a Pauline letter.
Modern scholars debate the authorship of several Pauline epistles, especially the Pastoral Epistles: 1 Timothy, 2 Timothy, and Titus. The traditional count nevertheless remains thirteen because church tradition and the canonical arrangement associate all of them with Paul.
Paul’s letters address communities and individuals across the eastern Mediterranean during the first Christian century.