Part 3B: Christological Heresies
Think of the impact Trichotomy would have, if consistently held, on our Christology. Orthodox Christianity has always affirmed the Hypostatic Union of Christ. This means that Christ is fully God and fully man - two distinct natures, not intermingled - by a mystery of divine wisdom hypostatically united in One Person. Christ is not a human person and a Divine Person sharing a body.
Try to square this with Trichotomy and you rush headlong into blasphemous heresy. You will end up trying to divide Christ in an Apollonarian way. Apollonarius taught that Christ was a human body that had the Second Person of the Trinity, the Logos, in the place of a normal human soul. If you do this, you must postulate two spiritual natures in Christ and you don't want to know where that will lead you. A human nature without a human soul is a non-entity. It is semantic nonsense. If Christ was not fully human, He could not have died for humans. His death is efficacious for the elect precisely because He is one of us. A human without a soul is not a human. Christ had to be human to atone for humans.
The simple fact is, there is no way to square Trichotomy with biblical Christology. Either you end up denying or downplaying Christ’s deity, His humanity or you create a schizophrenic Christ – each option as heretical and blasphemous as the others. Mention is made of Jesus’ soul being troubled in Matthew 26:38. In John 11:33 and 13:21, we read that His spirit was troubled. The same emotion is described in these three texts, again reaffirming what we claimed before about the interchangeable nature of these words. But try dealing with any of those passages from a Trichotomist view point and you head straight down the toilet theologically. There is no way to handle those passages from a Trichotomist view point without ending up in one of the Christological heresies of the first 4 centuries of Church history.