Building on the work of Cyril of Alexandria, Thomas Weinandy relates a thought-experiment on the mystery of the Incarnation in his book Does God Suffer?:
It may be helpful to illustrate this understanding of the communication of idioms with an example. Allow me to use an example that I pose to my students, which has come to be known in some circles as ‘Dr. Weinandy’s carrot example.’
Jesus goes to Martha’s, Mary’s and Lazarus’ home for dinner. Martha serves as a starter (to use the English term) raw carrots with garlic dip (a yet to be discovered American culinary invention). Jesus ate the carrots. Who was it who ate the carrots? It was the Son of God who ate the carrots. Was he eating the carrots as God or as man? Obviously, he was eating the carrots as man. God as God cannot eat carrots for he does not have teeth, a mouth, a stomach, etc. Lazarus also ate the carrots, but unfortunately he ate a rotten carrot and died of food poisoning. Four days later Jesus returned and raised Lazarus from the dead. Who was it who raised Lazarus from the dead? It was the Son of God who raised Lazarus from the dead. But did he raise Lazarus from the dead as God or as man? At this juncture there is silence among the students. Inevitably the more pious students first break the silence by saying that Jesus raised Lazarus from the dead ‘as God.’ I remain silent. Then some brave soul, usually a girl, will hesitantly whisper, almost inaudibly, ‘as man.’ That is precisely the correct answer. Within the Incarnation the Son of God never does anything as God. If he did, he would be God acting in a man. This the Incarnation will never permit. All that Jesus did as the Son of God was done as a man – whether it was eating carrots or raising someone from the dead. He may have raised Lazarus from the dead by his divine power or, better, by the power of the Holy Spirit, but it was, nevertheless, as man that he did so. Similarly, the Son of God did not suffer as God in a man, for to do so would mean that he was not a man. The Son of God suffered as a man. (205)
That phrase in the first paragraph–“the communication of idioms”–is a technical phrase that demands, as Weinandy has it elsewhere, “that it be truly the full divine Son of God who is man, that it be truly a complete man that the Son of God is, and thus that the Son of God actually does exist as man” (190).
And all of this to get at and express what he calls the personal/existential conception of the Incarnation: “Jesus is the person of the Son existing as a man” (197).