Godhead as the Father, Son and Holy Spirit: Eternal or Convenient?

Is the nature of God, revealed as the Father, Son, and Holy Spirit (1 Cor. 8:6, 2 Cor. 3:17, Col. 2:9, John 1:14) an eternal arrangement or merely a convenient one? This question is significant because it highlights the a key difference of significance between the Trinitarian and Unitarian positions on the nature of God. The Trinitarian view holds that Father, Son, and Holy Spirit are united as three persons in one Godhead. In contast, Unitarianism view the titles of Father, Son, and Holy Spirit as manifestations of the single supreme creator God.  Thus, it is easy to see why some might be led to view this framework as a purer version of monotheism relative to Trinitarianism. Unitarianism, as well as related frameworks  such as Sabellianism and Monarchianism are also attractive, in an apologetic setting in that it is easier to counter when pressed by the interrogations of monotheistic sceptics, who deny that trinitarianism teaches the oneness of God. In contrast, Trinitarians commonly struggle to explain the doctrine when challenged by doubters from other Abrahamic religions.

However, the Unitarian conception raises crucial concerns about the eternal role of the Son and the Holy Spirit in the Godhead. The role of the Son appears to be primarily a consequence of man's fall and a convenient arrangement designed to achieve the salvation of man. Consequently, such a provisional arrangement does not preclude a different manifestation in the future. It also flows logically, that in the eternal steady state, the Son and the Holy Spirit would cease to disappear. Paradoxically, given the temporary nature of the Father, Son, and Holy Spirit relationship, Unitarian Christianity also quickly allows for a logical inclusion of non-monotheistic frameworks. Any deistic revelation could be accommodated as a temporary manifestation of the eternal creator. The Trinitarian doctrine, with its belief in the eternal nature of the Father, Son, and Holy Spirit, provides a more coherent understanding of God's nature in light of the scriptures.