Communicatio Idiomatum: The Communication of Attributes.

In Mark 13:32 and Matthew 24:36, Jesus answers the disciples' question concerning the timing of the end of the world with these words: "But of that day and that hour knoweth no man, no, not the angels which are in heaven, neither the Son, but the Father" (Mark 13:32, see also Matt. 24:36; Acts 1:7). How can Jesus, who is God in the flesh, say that he does not "know" something? God is omniscient, yet, here Jesus, the second member of the Triune Godhead, says, "only the Father knows the day and the hour of the Final Judgment." How can this be? When approaching this text, theologians will typically discuss the Communicatio Idiomatum, a Latin phrase meaning "The communication of attributes." This discussion seeks to answer the question, "What is the relationship of the attributes of Christ to one another"? In particular, what is the relationship of the attributes of Christ in His divine nature to the attributes of Christ in His human nature? In other words, how do the two natures of Christ relate to one another? Take, for example, Jesus' human body. It would be absurd to think of Jesus' human body as omnipresent. But we know from scripture that God is omnipresent. How do those two relationships work together? Is Jesus both localized in His human body and also ubiquitous as God? We may say this, what is true of Jesus' human nature may or may not be said of Jesus' God nature, vice versa. As He walked on earth, Jesus willingly confined Himself to a specific localized place in His human nature and body. Yet, while Jesus willingly confined Himself in his Human nature and in His human body (by confinement we mean to a localized place in His body) in His God nature, He is and never ceased to be omnipresent. ​

In Jesus' death, we see another example. We know from scripture that Jesus suffered and died a horrible death on the Cross of Calvary. But does that mean that God died? Is not God self-existent? How can God die? Does He cease to be God for a moment if He passes for a moment or three days? No! God cannot die! That again would be (philosophically speaking) absurd. Thus we conclude, that Jesus in His human nature, truly and physically died and was buried. Still, concerning His divine nature, He continued to be the ever-living God, sustaining all creation. Therefore, while what is true of Jesus' human nature may not be true of Jesus' divine nature, and what is true of Jesus' divine nature may not be true of Jesus' human nature, we can conclude that what is true of Jesus' divine nature and Jesus' human nature is true of Jesus himself. Thus, Jesus can in His human nature rightly say, "But of that day and that hour knoweth no man, no, not the angels which are in heaven, neither the Son, but the Father" (Mark 13:32), while at the same time, in His divine nature "know all things." Jesus, as a man, has a true human nature and a true human mind. But Jesus is more than just man; He is the God-man. Thus, in His earthly ministry as the incarnate Son of God, He "willingly" did not avail himself of the information He "does have" as God in His divine nature. Jesus is both fully Divine and fully human, and both divine attributes and human attributes are present in the person of Christ. Much of this is a mystery, and we do not conclude to understand this relationship in all its fullness, but what we can conclude is that there is no contradiction in Holy Writ. Better to trust in the Word of God, than the faulty and often erroneous mind of man.