The doctrine of the Trinity has been a focal point of Christian thinking throughout Church history. While the term “Trinity” does not appear in the biblical text, it is still a vital Christian doctrine. The doctrine, however, has not come without controversy. Various understandings of the doctrine have been presented throughout Church history. Tertullian (ca. 160-220 AD) and Augustine (354-430 AD) represent two of the foremost theologians to discuss the issue. Tertullian was one of the first to thoroughly examine the doctrine. He coined the terms “substance” and “person” in his discussion of the doctrine. These terms would come to have a lasting impact on Christian theology. The council of Nicaea would show this commitment to Tertullian’s distinctions. Augustine also reflects his debt to Tertullian’s ingenuity yet makes significant moves to further develop the doctrine. Each of the theologians wrote in a particular context challenging the heretics of their day. They used biblical argumentation and their own philosophical commitments to present their understanding of the doctrine. This paper examines Tertullian’s use of the terms and then compares and contrasts them with Augustine’s use.


Ph.D. student at Liberty University studying Theology & Apologetics with a focus in Church History.

Andrew P. Hillaker