Ignatius of Antioch is considered one of the three most important of these, together with Clement of Rome and Polycarp.

Ignatius of Antioch is considered one of the three most important of these, together with Clement of Rome and Polycarp. Although the authenticity of his letters has been questioned, they continue to serve as an example of early Christian theology, and address important topics including ecclesiology, the sacraments, and the role of bishops.