The question of the divinity and humanity of Jesus Christ has been one of the most important questions for Christianity. Judaism and Islam may affirm his humanity but only Christianity professes his divinity. If only a man, then how could he have performed miracles and, after being dead for three days himself, rise from the grave? If God alone, how could He have suffered and died, since Divinity is immortal and feels no pain?
Catholic Christianity, as well as Eastern Orthodox and Protestant Christianity, firmly believe that Jesus Christ is “true God and true Man” as stated in the Nicene Creed of 325 AD. What is not taught is that Jesus is only half human and half divine. He is not a hybrid and, unlike Mr. Spock of Star Trek, He is not the offspring of two species. While His mother is very much human, He has no biological human father since it was by the power of the Holy Spirit that He was conceived in the womb (Luke 1:35). Nine months after His conception, Jesus was born and “He grew and became strong, filled with grace and wisdom” (Luke 2:40).
The Church believes that in His human nature, Jesus had a fully human body with five senses. He got hungry, ate, slept, laughed, cried, felt pain, and could die like any man or woman. Jesus was not like Superman from another planet who had a super body. His human nature not only had a human body but also a human soul which possessed a human intellect and a human will.
Docetism was a heresy of the early church that denied the humanity and human nature of Christ. It maintained that Jesus only pretended to be human—that His divinity was real but His humanity was a phantasm or appearance. Arianism (promoted by a priest named Arius) was a heresy of the same period that denied the divinity and divine nature of Christ. It maintained that Jesus was the “adopted” Son of God but that He only had a similar substance to God the Father, and not the same substance.
The Council of Nicea (325 AD) condemned Arianism and solemnly defined that Christ was consubstantial to God the Father in his divine nature as God the Son. The term the council used was homoousios (same substance) as opposed to the one used by Arianism, homoiousios (similar substance). Homoousios explained how Jesus could perform miracles by using His divine nature and how He was able to suffer and die for our sins by using His human nature.
Jesus had human emotions the same way He had human DNA, genes, chromosomes, flesh and blood, hormones, organs, etc. Only in His divine nature did He enjoy divine powers, such as the ability to walk on water; change water into wine; give sight to the blind; cure the deaf, the mute, and lame; expel demons; and raise the dead.
Since Adam and Eve committed the first sin, human nature had been wounded but not destroyed. What is wounded can be healed and is redeemable and salvageable. What is corrupt and dead is beyond repair. Human nature alone could not atone for the sin since the offense against God was measured by the dignity of the one who was offended. Only divinity could save and redeem mankind, but only humanity could suffer, die, and make the sacrifice. A God-Man, someone true God and true Man, could be the only one to both offer the sacrifice (priest) and be the sacrifice itself (victim).