Understanding the "Who" and "What" of Jesus?
Holy Apostles College & Seminary
by Allison Ramirez
Dr. Marianne Siegmund PHS 607: Philosophy for Theologians
15 June 2022
One cannot grasp the magnitude of what Jesus accomplished for us without first understanding the essence of who and what he is. To begin answering the who (or personhood) of Jesus’ identity, Cardinal Joseph Ratzinger (Pope Benedict VI) in his article, “Concerning the notion of person in theology,” writes: “God is ‘una substania-tres personae,’ [which means] one being in three persons.”  The three persons who make up this one “being” we call God are the Father, the Son, and the Holy Spirit – all equally able to claim the title God – but distinct in who they are as persons. Thus, from the Christian perspective, Jesus is who we would call “the son,” the second person in the three-person Trinity that encompasses the essence of God.
Now what do we mean when we say Jesus is one of the persons of the Trinity? “The phrase una substania-tres personae was the first time that the word “person” entered intellectual history with its full weight,”  as Ratzinger explains, and that this above terminology was largely pre-laid by the Patristic theologian Tertullian. In looking at the meaning of the word, theologically, when we say person, we can begin with one of the earliest definitions from Boethius, who defined personhood as “an individual substance of a rational nature”  Though this definition did not account for the relational nature of person that had to be later developed. Ratzinger tells us: “According to Augustine and late patristic theology, the three persons that exist in God are in their nature relations.”  Unlike Boethius, who posited a view of personhood that was of an “individual substance,” Ratzinger expounds upon the definition in light of later tradition in writing that person is “not substances that stand next to each other, but they are real relations, and nothing besides.” Ultimately, “In God, person means relation.” 
Modern-day Theologian and Orthodox Bishop, Kallistos Ware, makes an observation relevant to the relational reality of the three persons of God, of which Christ is the second, when he writes: “There is in God genuine diversity as well as true unity. The Christian God is not just a unit, but a union, not just unity but community.”  In other words, the three persons of the Trinity are not a singular unit in which there is no distinction. Instead, the three persons form a self-giving community where there can exist both ‘genuine diversity’ as well as ‘true unity’.
Ware’s observation of the ‘communal reality’ of persons existing in the Trinity also lends into our next distinction to be made of Jesus, which is in regard to the what of his identity, more specifically, his nature. Nature is according to St. Thomas Aquinas, “the essence of a being considered as the principle of activity. Also the substance of a thing as distinguished from its properties, considered as the source of its operations.” Aristotle has a similar definition, noted by Aquinas, as: “Nature is the principle of motion and rest, in those things in which it is essentially, and not accidentally.” 
According to Fr. John Hardon’s Modern Catholic Dictionary, the theological term ‘hypostatic union’ helps describe how Jesus embodies what is defined above as nature. Hypostatic union according to the dictionary is defined: “with reference to the Incarnation to express the revealed truth that in Christ one person subsists in two natures.”  The Church teaches that Jesus is one person with two natures. Bishop Kallistos Ware, who was mentioned already above, states that “The fourth council (Chalcedon, 451) proclaimed that there are in Jesus Christ two natures, the one divine and the other human.” 
The council’s determination negated heresies of the time which claimed Jesus either had only a single, divine nature or that he had a “mixture” of two natures. Further expanding on these above points, Articles 468-469 of the Catechism of the Catholic Church state:
…The fifth ecumenical council, at Constantinople in 553, confessed that "there is but one hypostasis [or person], which is our Lord Jesus Christ, one of the Trinity." … The Church thus confesses that Jesus is inseparably true God and true man. He is truly the Son of God who, without ceasing to be God and Lord, became a man and our brother.” 
The philosophical importance of the human person and how it relates to what Jesus accomplished is that Jesus cannot be person on his own, but that his very personhood is inseparable from his being in perfect relational and self-giving love with the Father and the Holy Spirit. Additionally, Jesus cannot have authentically completed the mission for which he was sent –thus to be like us in all things but sin so as to redeem and make possible for us a true return to the father— if he were not fully divine (fully God) while also existing simultaneously as fully human. Thus lies the significance of his two natures. In both Jesus’ personhood and nature, there appears the beautiful mystery of unity and diversity, godhood and manhood, that we are invited into also as beings created in the image and likeness of the Trinitarian God. “Let us make man in our image, after our likeness.” 
Bishop Kallistos Ware, The Orthodox Way, Rev. ed. (New York: St. Vladimir’s Seminary Press, 1979).
Catechism of the Catholic Church. 2nd ed. Washington, DC: United States Catholic Conference, 2000.
John A. Hardon, “Modern Catholic Dictionary,” Dictionary of Terms - A (therealpresence.org), 1999.
Joseph Cardinal Ratzinger, “Concerning the Notion of Person in Theology” in Communio: International Catholic Review (Fall, 1990; Vol. 17.3).
The Holy Bible: Revised Standard Version. New York: Collins, 1971.
Thomas Aquinas, Summa theologiae, q. 29, a. 1, at New Advent, www.newadvent.org.
 Joseph Cardinal Ratzinger, “Concerning the Notion of Person in Theology” in Communio: International Catholic Review (Fall, 1990; Vol. 17.3), 440.  Ratzinger, “Concerning the Notion of Person in Theology,” 440. Thomas Aquinas, Summa theologiae, q. 29, a. 1, at New Advent, www.newadvent.org..  Ratzinger, “Concerning the Notion of Person in Theology,” 444.  Ratzinger, “Concerning the Notion of Person in Theology,” 444. Bishop Kallistos Ware, The Orthodox Way, Rev. ed. (New York: St. Vladimir’s Seminary Press, 1979), 27.  ST, q. 29, a. 1  ST, q. 29, a. 1  John A. Hardon, “Modern Catholic Dictionary,” Dictionary of Terms - A (therealpresence.org), 1999.  Bishop Kallistos Ware, The Orthodox Way, 71. Catechism of the Catholic Church, 2nd ed. (Wa, DC: United States Conference, 2000) 118.  Genesis 1:6 (RSVCE)