Source: https://secondexodus.com/home/words/hypostatic-union/
Timestamp: 2019-04-18 10:52:58+00:00

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The union of the divine and human natures in the one divine Person (Greek: hypostasis) of the Son of God, Jesus Christ.
§ 252 The Church uses (I) the term “substance” (rendered also at times by “essence” or “nature”) to designate the divine being in its unity, (II) the term “person” or “hypostasis” to designate the Father, Son, and Holy Spirit in the real distinction among them, and (III) the term “relation” to designate the fact that their distinction lies in the relationship of each to the others.
§ 464 The unique and altogether singular event of the Incarnation of the Son of God does not mean that Jesus Christ is part God and part man, nor does it imply that he is the result of a confused mixture of the divine and the human. He became truly man while remaining truly God. Jesus Christ is true God and true man. During the first centuries, the Church had to defend and clarify this truth of faith against the heresies that falsified it.
§ 465 The first heresies denied not so much Christ’s divinity as his true humanity (Gnostic Docetism). From apostolic times the Christian faith has insisted on the true incarnation of God’s Son “come in the flesh.” But already in the third century, the Church in a council at Antioch had to affirm against Paul of Samosata that Jesus Christ is Son of God by nature and not by adoption. The first ecumenical council of Nicaea in 325 confessed in its Creed that the Son of God is “begotten, not made, of the same substance (homoousios) as the Father”, and condemned Arius, who had affirmed that the Son of God “came to be from things that were not” and that he was “from another substance” than that of the Father.
We confess that one and the same Christ, Lord, and only-begotten Son, is to be acknowledged in two natures without confusion, change, division or separation. the distinction between the natures was never abolished by their union, but rather the character proper to each of the two natures was preserved as they came together in one person (prosopon) and one hypostasis.
The Son of God worked with human hands; he thought with a human mind. He acted with a human will, and with a human heart he loved. Born of the Virgin Mary, he has truly been made one of us, like to us in all things except sin.
§ 471 Apollinarius of Laodicaea asserted that in Christ the divine Word had replaced the soul or spirit. Against this error the Church confessed that the eternal Son also assumed a rational, human soul.
§ 473 But at the same time, this truly human knowledge of God’s Son expressed the divine life of his person. “The human nature of God’s Son, not by itself but by its union with the Word, knew and showed forth in itself everything that pertains to God.” Such is first of all the case with the intimate and immediate knowledge that the Son of God made man has of his Father. The Son in his human knowledge also showed the divine penetration he had into the secret thoughts of human hearts.
§ 474 By its union to the divine wisdom in the person of the Word incarnate, Christ enjoyed in his human knowledge the fullness of understanding of the eternal plans he had come to reveal. What he admitted to not knowing in this area, he elsewhere declared himself not sent to reveal.
§ 476 Since the Word became flesh in assuming a true humanity, Christ’s body was finite. Therefore the human face of Jesus can be portrayed; at the seventh ecumenical council (Nicaea II in 787) the Church recognized its representation in holy images to be legitimate.
§ 477 At the same time the Church has always acknowledged that in the body of Jesus we see our God made visible and so are caught up in love of the God we cannot see. The individual characteristics of Christ’s body express the divine person of God’s Son. He has made the features of his human body his own, to the point that they can be venerated when portrayed in a holy image, for the believer who venerates the icon is venerating in it the person of the one depicted.
§ 478 Jesus knew and loved us each and all during his life, his agony and his Passion, and gave himself up for each one of us: “The Son of God … loved me and gave himself for me.” He has loved us all with a human heart. For this reason, the Sacred Heart of Jesus, pierced by our sins and for our salvation, is quite rightly considered the chief sign and symbol of that love with which the divine Redeemer continually loves the eternal Father and all human beings” without exception.

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