26.

 In order to make theosis possible, what nature would Christ have to possess?

            Christ must be — and is — both fully God and fully man. The textbook goes on to note that:

Each heresy in turn undermined some part of this vital affirmation. Either Christ was made less than God (Arianism); or His manhood was so divided from His Godhead that He became two persons instead of one (Nestorianism); or He was not presented as truly man (Monophysitism, Monothelitism).

In response to these four heresies that attacked God's revelation, the Ecumenical Councils defended the truth that Christ is fully God and fully man.