The Father possesses essence, hypostasis, and ontological existence. Everything that is essentially true about Him, encompassing all His attributes, is represented in Christ. This concept is generally accepted, even outside Trinitarian belief. However, the doctrine of the Trinity takes this further by introducing the idea of homoousios, which posits that the essence called 'God' is shared among three persons and exists as an entity beyond the Father alone.
The rationale behind this doctrine appears to stem from a desire to logically and philosophically combine elements of Hebrews 1:3. This approach seems influenced by Neoplatonism. By examining the essence of the Father and its representation in the Son, one might be tempted to view the essence as common to both, akin to Plato's Theory of Forms and the Allegory of the Cave, where form and representation are distinct yet related.
However, this interpretation skips over a critical detail: the essence belongs to the Father and is only represented by the Son. Claiming that the essence is truly common to both is misleading. The Son represents the Father's essence; they do not share it. This subtle distinction is overlooked in the philosophical techniques seen in the works of Tertullian and his Neoplatonist successors. Their enthusiasm for applying Platonic thought led them to neglect important details, which, over time, contributed to theological errors.
This issue became apparent when critics pointed out that the early Trinitarians blurred the distinctiveness of the persons within the Godhead. To address this, they eventually clarified their doctrine by introducing the concept of distinct "personas," which was partly a response to various schisms and controversies.
