The immortality of the soul and the resurrection of the dead are two of the most widely treated topics among early and medieval Christian writers. I argue that the foundational Christian doctrine of the resurrection of the body is not reconcilable with the Platonic concept of the immortality of the soul; likewise the idea of the soul's immortality seems to shift and eventually diminish in value throughout the early and medieval periods, as shown through the prayers and teachings of the church. Looking at the origins of somatic resurrection and its difference from Platonic immortality, the New Testament and Patristic teachings on the two, the prayers and funeral traditions of the post-schism Church, and the Speculum Humanae Salvationis manuscript, I will attempt to redefine Christian immortality with respect to Christian resurrection from a philological perspective. While the resurrection of the body is an uncontested doctrine among believers, the immortality of the Christian soul takes on different meanings over time, and requires standard definition. I find the term "immortality" insufficient for relating Christian immortality and psychosomatic resurrection. Therefore, I shall endeavor to create a new term for Christian psychosomatic eternal life, with the resurrection of the body acting as the focal point for redefinition – a term that encompasses the properties of the soul, the truths of Christian resurrection, and an eschatological hope for the Second Coming of Christ.