Abstract
This chapter sets the stage for the philosophical argumentation to come in the following chapters. It discusses the importance of the ecumenical councils to many Christian denominations. It then goes on to explicate the teaching of the first seven ecumenical councils concerning Christ. Next, it provides an understanding of the metaphysical terms and concepts employed in the councils, including “nature,” “supposit,” and “person.” This understanding is broadly Thomistic. It differentiates multiple meanings that the term “nature” might have, and it discusses which usage fits best with the conciliar evidence. Finally, it discusses the predicates we might rightly say of the human nature that Christ assumed in the incarnation.