According to the Catholic Church, is Jesus a man, or does He rather have a human nature without being a man?
It is explained in the Catechism of the Catholic Church:
IV. How is the Son of God Man?
470 Because "human nature was assumed, not absorbed",97 in the mysterious union of the Incarnation, the Church was led over the course of centuries to confess the full reality of Christ's human soul, with its operations of intellect and will, and of his human body. In parallel fashion, she had to recall on each occasion that Christ's human nature belongs, as his own, to the divine person of the Son of God, who assumed it. Everything that Christ is and does in this nature derives from "one of the Trinity".
The Son of God therefore communicates to his humanity his own personal mode of existence in the Trinity. In his soul as in his body, Christ thus expresses humanly the divine ways of the Trinity:
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.
Christ's soul and his human knowledge
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.
472 This human soul that the Son of God assumed is endowed with a true human knowledge. As such, this knowledge could not in itself be unlimited: it was exercised in the historical conditions of his existence in space and time. This is why the Son of God could, when he became man, "increase in wisdom and in stature, and in favour with God and man", and would even have to inquire for himself about what one in the human condition can learn only from experience. This corresponded to the reality of his voluntary emptying of himself, taking "the form of a slave".
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.108 What he admitted to not knowing in this area, he elsewhere declared himself not sent to reveal.
Christ's human will
475 Similarly, at the sixth ecumenical council, Constantinople III in 681, the Church confessed that Christ possesses two wills and two natural operations, divine and human. They are not opposed to each other, but co-operate in such a way that the Word made flesh willed humanly in obedience to his Father all that he had decided divinely with the Father and the Holy Spirit for our salvation.110 Christ's human will "does not resist or oppose but rather submits to his divine and almighty will."
Christ's true body
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.113
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."114 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".
The heart of the Incarnate Word
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,117 "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.
According to Catholicism, Jesus Christ is truly man and truly God, with a Divine nature and a human nature.
Jesus is the most important person who has ever lived since he is the Savior, God in human flesh. He is not half God and half man. He is fully divine and fully man. In other words, Jesus has two distinct natures: divine and human. Jesus is the Word who was God and was with God and was made flesh (John 1:1, 14). This means that in the single person of Jesus he has both a human and divine nature, God and man. The divine nature was not changed when the Word became flesh (John 1:1, 14). Instead, the Word was joined with humanity (Col. 2:9). Jesus’ divine nature was not altered. Also, Jesus is not merely a man who “had God within Him,” nor is he a man who “manifested the God principle.” He is God in flesh, the second person of the Trinity. “The Son is the radiance of God’s glory and the exact representation of his being, sustaining all things by his powerful word,” (Heb. 1:3). Jesus’ two natures are not “mixed together” (Eutychianism), nor are they combined into a new God-man nature (Monophysitism). They are separate yet act as a unit in the one person of Jesus. This is called the Hypostatic Union.
The following chart should help you see the two natures of Jesus “in action”:
He is worshiped (Matt. 2:2, 11; 14:33)
He was called God (John 20:28; Heb. 1:8)
He was called Son of God (Mark 1:1)
He is prayed to (Acts 7:59)
He is sinless (1 Pet. 2:22; Heb. 4:15)
He knows all things (John 21:17)
He gives eternal life (John 10:28)
All the fullness of deity dwells in Him (Col. 2:9)
He worshiped the Father (John 17)
He was called man (Mark 15:39; John 19:5)
He was called Son of Man (John 9:35-37)
He prayed to the Father (John 17)
He was tempted (Matt. 4:1)
He grew in wisdom (Luke 2:52)
He died (Rom. 5:8)
Other verses to consider when examining His deity are John 10:30-33; 20:28; Col. 2:9; Phil. 2:5-8; Heb. 1:6-8; and 2 Pet. 1:1.
1 Tim. 2:5 says, “For there is one God, and one mediator also between God and men, the man Christ Jesus.” Right now, there is a man in heaven on the throne of God. He is our advocate with the Father (1 John 2:1). He is our Savior (Titus 2:13). He is our Lord (Rom. 10:9-10). He is Jesus.
Jesus’ Two Natures: God and Man
Jesus is true man and true God, the two natures, each retaining its own properties, are united in one subsistence and one person.
Hypostatic Union, a theological term used with reference to the Incarnation to express the revealed truth that in Christ one person subsists in two natures, the Divine and the human. Hypostasis (upostasis) means, literally, that which lies beneath as basis or foundation. Hence it came to be used by the Greek philosophers to denote reality as distinguished from appearances (Aristotle, “Mund.”, IV, 21). It occurs also in St. Paul’s Epistles (II Cor., ix, 4; xi, 17; Heb., i, 3: iii, 14), but not in the sense of person. Previous to the Council of Nicaea (325) hypostasis was synonymous with ousia, and even St. Augustine (De Trin., V, 8) avers that he sees no difference between them. The distinction in fact was brought about gradually in the course of the controversies to which the Christological heresies gave rise, and was definitively established by the Council of Chalcedon (451), which declared that in Christ the two natures, each retaining its own properties, are united in one subsistence and one person (eis en prosopon kai mian upostasin) (Denzinger, ed. Bannwart, 148). They are not joined in a moral or accidental union (Nestorius), nor commingled (Eutyches), and nevertheless they are substantially united.
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