Paul's letters, also known as the Pauline epistles, are a collection of 13 books in the New Testament of the Christian Bible traditionally attributed to the apostle Paul. Written between 50 and 67 AD, these letters were addressed to various early Christian communities and individuals, providing guidance, instruction, and encouragement in matters of faith, conduct, and doctrine. Paul's letters cover a wide range of topics, including salvation, justification by faith, the role of the Holy Spirit, the relationship between Jews and Gentiles in the church, and the ethical implications of Christian living.