All of us know that 100 plus 100 equals 200, not 100. If a single being is at 100 and Jesus is a single being, then He must be 100, so how can He or could He be 200? What does all this mean? How could Jesus effectively be completely, 100% man, when He is completely, 100% God? This is usually a struggle when teaching about Jesus to anyone. I've been asked about it many times and in various ways.
From my study and experience, the number one thought that brings together His complete humanity with His complete Deity is the teaching that by becoming man Jesus gave up the free exercise of His attributes, a doctrine that centers on Philippians 2:7, which reads:
But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men.
The words "made himself of no reputation" translate two Greek words, eautou kenoo, the second of which translates into the four words, "made of no reputation." That second Greek word is the basis for a doctrine called, "kenosis." The two words, eautou kenoo, mean literally, "he emptied himself." If it means, "he emptied himself," of what did Jesus empty Himself?
The doctrine of kenosis says that when Jesus became man, He was still completely, 100% God, but He emptied Himself of the free exercise of His attributes. This is saying that He had all these attributes. He kept all of them. He did not exercise these divine attributes freely. This was an aspect of His condescension and humiliation, which is taught in Philippians 2:3-10.
The doctrine of kenosis has its one proof text in Philippians 2, but it also emerges from the Gospels. It makes sense of certain statements that don't complement the Deity of Christ very well. You read it and you ask, why? The doctrine of kenosis answers these, bringing harmony to all of these passages.
Consider God's attribute of omniscience. God knows everything. Many times Jesus shows omniscience. He can read people's minds. He knows what they're thinking in supernatural way (Matthew 9:4, 12:25, Mark 2:8, Luke 11:17, and John 13:5). Jesus told the woman at the well things that He could not have known about her unless He was God (John 4). At the same time, in the Olivet Discourse Jesus said in Mark 13:32,
But of that day and that hour knoweth no man, no, not the angels which are in heaven, neither the Son, but the Father.
Jesus didn't know this. Only the Father knew it. This is an example of Jesus limiting the free exercise of His attributes. There were other ways that He did, but you get the point.
Theologians call the union in Jesus of the Divine and the human the hypostatic union. To make sense of the hypostatic union means exploring how He did divine works like forgiving sin (Luke 7:48), while doing things as a human being not characteristic of God, such as sleeping (Mark 4:38), weeping (John 11:35), and hungering (Mark 11:12). Luke 2:52 says Jesus grew in wisdom. If Jesus was omniscient, how could that be true?
The purpose of God necessitated the incarnation. Jesus must become man, while remaining fully God. He would not fulfill the Davidic covenant without a human lineage. Jesus rose from dead with Divine power, but He was dead because He was human. As a human He could pay sin's price for humans and yet rise again as God. Still a tension exists.
Jesus said in Luke 22:42, "Not my will, but thine, be done." Wait a second. Wasn't the will of the Father and the will of the Son exactly the same? They had the same will, right? This is where we understand something further in the doctrine of kenosis. As a human being, Jesus must submit His will, His human will, to the will of the Father. As a human being, Jesus must learn obedience. That might sound impossible, but a verse teaches this. Hebrews 5:8 says,
Though he were a Son, yet learned he obedience by the things which he suffered.
Did Jesus need to learn anything? Yes. He didn't need to learn obedience as God. He and the Father forever had the same will. His subservience to the Father's will, His submission to the Father's will, was an aspect of His humanity. Like other human beings, He learned that. This was again part of His emptying Himself of the free exercise of His attributes.
For awhile and today still an argument exists concerning the eternal subordination of the Son to the Father. I understand why people have believed it. The main argument against, and I agree with it, is the following. As both God in essence, the Father and the Son cannot have two wills. They do not have two wills. The obedience of the Son, His earthly submission to the Father, represents kenosis, Jesus' emptying Himself of the free exercise of His divine attributes.
God is one, so He has one will, not two. As human, Jesus learned obedience. He always obeyed, but that subordination was not eternal. The subordination of the Son to the Father does not extend previous to His incarnation. This is a repercussion of Jesus simultaneously being both completely 100% God and completely 100% Man.