Article by Erik Raymond – original source here

Recently someone who is just beginning to investigate Christianity asked me an important question. As they are wading through the biblical data, the question came up, Why was Jesus both human and divine? Is this an important detail?  

This is an important question. It’s vital that we understand not only that Jesus was truly God and fully man, but also why it is important. 

I have found the Heidelberg Catechism quite helpful in its concise explanation. 

On question 16 we read,

Q:  Why must he be a true and righteous man?

A:   He must be a true man because the justice of God requires that the same human nature which has sinned should pay for sin. He must be a righteous man because one who himself is a sinner he cannot pay for others.

The answer here is focusing on the need for a real human nature. Why? Because the penalty for sin requires suffering in body and soul. And only a human can do this (cf. Heb. 2:14; John 12:27). Jesus did not only share in our nature but also he had to identify with us in the experiences of the fall (Heb. 2:17-18). But it was essential that Christ himself did not sin in this identification with us. Otherwise, how could he pay for our sin? Berkhof writes, “Only such a truly human Mediator, who had experimental knowledge of the woes of mankind and rose superior to all temptations, could enter sympathetically into all the experiences, the trials, and the temptations of man (Heb. 2:17, 18; 4:15-5:2) and be a perfect human example for his followers (Matt. 11:29; Mark 10:39; John 13:13-15; Phil. 2:5-8; Heb. 12:2-4; 1 Pet. 2:21).  L. Berkhof, Systematic Theology, p. 319.

In short, the answer is Jesus had to be a man so that he could identify with us, suffering in our place and sympathizing with us in our weakness. 

On question 17 we read,

Q:   Why must he also be true God?

A:    So that, by the power of his divinity, he might bear the weight of God’s anger in his humanity and earn for us and restore to us righteousness and life. 

This answer focuses on the power coming from his divine nature. There is no way any mere human could bear and fully satisfy God’s wrath. By nature, this wrath is infinite in quality. In order to bear the weight of wrath, it is essential that the Savior be divine. But also, in order to satisfy this wrath, he had to offer a sacrifice of such a value that God would be pleased to accept it. Only Christ as God could bring a sacrifice of infinite and eternal value to God that he would propitiate heaven’s wrath. By virtue of his divine nature, he is able to earn for us eternal life and favor with God. Finally, the divinity of Christ means that he is able to be raised from the dead (after conquering it) and therefore apply the benefits he has earned for us. 

In short, the answer is, Jesus had to be truly God so that he could satisfy God’s wrath and secure for us true righteousness and life. 

More could be said here but certainly not less. 

If you like shorthand categories:

• The Redeemer had to be truly human: in order to suffer and sympathize.
• The Redeemer had to be truly divine: in order to satisfy and secure.