Early Christian Thinkers: The Lives and Legacies of Twelve Key Figures. by Paul Foster. This book introduces twelve key Christians from the second and third centuries, a formative period for the Church. These figures are: Justin Martyr, Irenaeus, Tatian, Theophilus of Antioch, Clement of Alexandria, Tertullian, Perpetua, Origen, Hippolytus, Cyprian, Gregory Thaumaturgos and Eusebius. Each chapter is self-contained and requires no preliminary knowledge of the figure under discussion, making this an ideal book for laity and for undergraduates studying Christian origins or Patristics.