The Hypostatic Union had a profound effect on Jesus’ human nature, as he is both true man and, also, God. Jesus is not a human person like us, but a divine Person.
Jesus Christ of Nazareth is the founder and object of the Catholic Church. He is both true God and true man. Because he is God, we worship him as our Creator and Redeemer; because he is also man, he is our brother and like us in all things, sin alone excepted. In Catholic theology, the union of the divine nature and the human nature is explained as taking place in the Person of Jesus, who is the Second Person of the Blessed Trinity, the Word of God. This is known as the “Hypostatic Union.” The word, hypostatis, is a Greek word which means “person.”
The Hypostatic Union had a profound effect on Jesus’ human nature. Jesus Christ is a true man, but, because he is also God, he is no ordinary man. It is important to remember that Jesus is not a human person like us; he is a divine Person. Because of the Hypostatic Union, Jesus’ human nature was endowed with an abundance of supernatural gifts; in fact, he has the perfection of all the virtues; St. John says that he is “full of grace and truth” (John 1:14). This raises questions about his human knowledge, human will, and human power.
There is an ancient tradition in the Church, going back to the early Fathers. The human soul of Jesus is united to the Word of God, possessing the Beatific Vision of God from the first moment of his existence, in the womb of his mother, the Virgin Mary. The Beatific Vision of God is absolutely supernatural; it is granted to the angels in heaven, and to the saints in heaven. What the Fathers and theologians say is that Christ’s soul possessed this vision of God from the first moment of its union with the divine Person of the Word, that is, from its conception in Mary. This means that Jesus was, at the same time, both a pilgrim on earth like us, and a possessor of the immediate vision of God, like the blessed in heaven. One of the consequences of his immediate vision of God is that he did not have the theological virtues of faith and hope, since faith and hope cease once there is vision and possession of God.
There are several indications in the New Testament that Jesus has immediate knowledge of the Father. Thus, we read in John 1:17-18, “…grace and truth came through Jesus Christ. No one has ever seen God; the only Son, who is in the bosom of the Father, he has made him known.” Jesus also says, in John 8:55, “I know him (the Father). If I said, I do not know him, I should be a liar like you; but I do know him and I keep his word.”
That Jesus had the Beatific Vision, from the moment of his conception, is a conclusion that the Fathers of the Church and theologians, like St. Thomas Aquinas, arrived at by examining who and what Jesus is. The Beatific Vision is the consummation of sanctifying grace; also, the attachment of the soul to God, through grace and glory, is an accidental union, or perfection, of the created soul. The attachment of Christ’s soul to God, however, is a substantial union because it is hypostatically united to the Word of God. Such a substantial union is more intimate than the union of the saints in heaven with God. Thus, if Christ’s soul on earth was already more intimately united to God than the blessed are in heaven, it follows that it must have, at least, the same immediate knowledge of God that the saints and angels have.
St. Thomas also argues that, since by Christ’s life and death, he is the source of salvation and heaven for all mankind, he must have what he gives to others. Since he communicates the Beatific Vision to others, he must have it himself, because no one can give what he does not have.
According to Hebrews 12:2, Jesus “leads us in our faith and brings it to perfection.” If he leads us, and perfects us in faith, then he knows perfectly what he is doing, and does not himself walk in the darkness of faith, as I mentioned above. The perfection of the knowledge and self-consciousness of the man, Jesus, can be explained only by the fact that he possessed immediate knowledge of the divinity with which he was substantially united.
In concrete terms, this means that Jesus’ soul had the Beatific Vision of God from the first moment of its existence. He already had, in this life, what we hope to attain in the next life.