The understanding of the Holy Trinity has been a source of controversies for many centuries in the Church. It has led to developments of various heretical positions as well. St. Basil in his Epistle to Gregory his brother attempts to clarify this mystery candidly with the hope of maintaining orthodoxy in its understanding. However, he forewarns that no concise and conclusive explanation can be given. It remains a mystery: “It is to no avail to press a definite conception upon a spiritual being, because we are persuaded that it is above all conception.” (St. Basil’s Epistle 202) The two terminologies that feature prominently in this clarification are ‘hypostasis’ and ‘ousiai’. The catholic encyclopedia defines hypostasis as that “which lies beneath as a basis or foundation.” In the etymological sense, this description would be the equivalent of the Latin’s Substancia. However when used analogously in reference to the Divine being, further clarification and distinction is necessary as we are going to see. Pope Benedict XVI would later use this understanding as a spring board to launch an explanation of the person of Jesus Christ in the encyclical Spe Salvi. (2007)
In the first paragraph St. Basil sets the record state by stating that while it is conceivable to identify the three ‘hypostases’ in the God head it is not right to talk of three ‘ousiai’. (196) The emphasis in this aspect points to the fact that even though there are three manifestations of the God head, there remains only one God. St. Basil explains that the separate existence of all the three hypostases cannot be independently perceived. “In whatever manner the notion of the Father’s being is understood by you, thus also will you conceive of the Son, and the same way also of the Holy Spirit. For the principle of uncreatedness and incomprehensibility is one and the same of the Father and the Son and the Holy Spirit. (204) The fact that we can conceive of the three traits as distinct but not separate, points to a comprehensive unity within the Trinity. This hypostatic unity is what St. Basil refers to when he writes: “For the Son, through whom are all things and with whom the Holy Spirit is always inseparably conceived is from the Father.” (206)
For further understanding of the relationship among the persons of the Trinity, St. Basil uses the illustration of the Rainbow. He writes that using this example, we can see clearly that even among creation, there exists a ‘possibility for united separation and disunited union.’ (212) This illustration is based on the fact that even though the rainbow has different colors, it remains only one rainbow. We cannot talk of the different colors of the rainbow as different types of rainbows nor can we conceive of a rainbow without any one of the colors contained therein. Using this analogy, St Basil thus makes a strong point of the possibility of the existence of three persons in one. He uses this analogy to conclude that; “The individual traits of the hypostases, as is evident with each given color of the rainbow, flash their light upon each of the other members of Holy Trinity in which we believe. (216)
As it had been hinted earlier, Pope Benedict XVI expounded on this notion of hypostasis as used in the New Testament. He focused on the letter to the Hebrews where the word is used in a manner most likely to suggest that it is coterminous with substance. (Spe Salvi 7). He points out that this was the understanding not only of the Fathers in the middle ages but also literal understanding when the Greek word is translated to Latin. Consequently, the term hypostasis thus understood indicates that the Christian faith is based on something foundational and indispensable. In reference to the text that the Pope quotes from the letter to the Hebrews in the New Testament, Faith is the ‘substance’ of things hoped for, the proof of things not seen. (Hebrews 11:1) This ‘substance’ when applied analogously to the life of Christ and the consequences of living Christian life takes on a new significance. New life in Christ becomes a life that is substantial and gives life to those who have hope and faith. (Spe SAlvi 8).
As a result, even though this alternative understanding of hypostasis appears to deviate slightly from St. Basil’s notion, they both point to the same truth. This is the truth, which holds that even though the persons of the trinity can be conceived of distinctly as in the person Christ, the underlying nature or rather ‘substance‘ stays the same. Thus, the Holy Father concludes: “In the New Testament this expectation of God, this standing with God, takes on a new significance: in Christ, God has revealed himself. He has already communicated to us the “substance” of things to come, and thus the expectation of God acquires a new certainty.” (Spe Salvi 9)
In Conclusion, we can say that the hypostatic union of the persons of the trinity is conceivable just as St. Basil explains using the illustration of the Rainbow. It is also reasonable to affirm as Pope Benedict does, that the coming of Jesus into the world, presented a new understanding of God’s existence since Jesus revealed another aspect of God while stating that He (Jesus) and the Father are one. On the whole, it is therefore possible to talk of three hypostases in the one Being of God. Any other indication of incomprehensibility in this area can then be attributed to the mysterious aspect of God because as St. Basil rightfully says, we cannot possibly have a perfect understanding of the Spiritual Being.