The Apostolic Fathers are the Christian writers from the first and second centuries who are thought to have known, some of the Apostles, or to have been so directly influenced by the apostles that their writings are considered echoes of genuine Apostolic teaching. Their writings form a link of tradition that binds these writings to those of the New Testament. Chief among the apostolic fathers are the three first-century Bishops: St. Clement of Rome, St. Ignatius of Antioch, and St. Polycarp of Smyrna, who were disciples of St. Peter and St. John. There are a number of works attributed to St. Clement although only his letter to the Corinthians (1 Clement) and possibly one of his homilies (2 Clement) are believed to be genuine. Ignatius and Polycarp also have a number of surviving letters, one of which includes the famous story of the martyrdom of Polycarp. Included in this collection is the Didache, an early doctrinal statement said to be composed by the twelve apostles before they went their separate ways to preach the gospel "to all nations." Also included is, the Epistle of Barnabas, which many have held to have been written by the Barnabas who is mentioned in the Acts of the Apostles. Some early Christian Bibles included these works, although later councils would leave them out of the canon of scripture.