The "New Testament Letters," also known as the Epistles, are a collection of writings found in the New Testament of the Christian Bible. These letters were primarily authored by early Christian leaders, including Apostle Paul, Peter, and John, to various churches and individuals. They address theological issues, provide guidance on Christian living, and offer encouragement to believers. There are 21 letters in total, with Paul's letters being the most numerous. Each letter varies in style and purpose, reflecting the specific needs of the recipients. Together, they play a crucial role in shaping Christian doctrine and practice.