The first thing we would be wise to understand is that the Son of God refers to an eternal being. The Son of God is a being who has no beginning, and has no end. We, as humans beings are eternal, we will live forever, but we did have a beginning. We were each created. The Son of God was never created because the Son of God is the 2nd person of the Trinity, that of the Father, the Son, and the Holy Ghost. The Son of God is God. All three persons of the trinity are eternal, and all three persons make up the One God. Therefore, the Son of God is God. 

Let’s look at who the Israelites followed when the left Eygpt. Who was with them as the went through the Red Sea and walked throughout the wilderness. Paul tells us in the book of Corinthians that it was Christ who was with them. Paul says that the Israelites “drank from the spiritual rock that traveled with them, and that rock was Christ” (1 Corinthians 10:4, NLT). That means that Christ is God, and this is when Jesus is called Jesus Christ, because Jesus refers to the man, the Christ refers to God. Jesus Christ, or Christ Jesus – God in man. So we have established that the Son of God is God, and that Christ is God, both are eternal and both are God. 

The Israelites travelled from Egypt many years before Jesus was born on earth, and yet Paul says that it was Christ who led them through the wilderness. This can only mean that Christ existed – as God – before He was born on earth as a man. Recall that the angel told Mary that she was to call the baby – Jesus. It was the baby, the man, who was called Jesus. Jesus refers to the humanity of God. 

And let us also remember the curious words that Jesus said when He spoke about Himself, to the Jews, about Abraham, Jesus said to the Jews, “before Abraham was even born, I am” (John 8:58, NLT). Jesus said that He existed before Abraham was even born. This can only mean that Jesus is God in the flesh, that God is living within the body of the man called Jesus. 

 So when we hear that phrase Son of God, what is that we should be thinking about? Should we understand that to mean that Jesus is the physical Son of God, or the that the Son of God refers to the 2nd person of the Trinity, or to both? 

Martha put it best in John 11 when she said about Jesus, ““Yes, Lord,” she told him. “I have always believed you are the Messiah, the Son of God, the one who has come into the world from God.” The Son of God appeared on earth in the body of a man. The Son of God was sent from heaven to earth. This is why Jesus often says that He was sent by God. Jesus is saying that He was sent from heaven as the Son of God. That is why we read in Galatians 4 God sent his Son, born of a woman, subject to the law.”

Did the Son of God exist in the Old Testament writings? Yes, but not as clearly as in the New Testament. In the Old Testament we read about God’s Son in Psalm 2 verse 12, where it says, “Submit to God’s royal son, or he will become angry”. This is the Old Testament, not the New Testament. And in the Old Testament the Psalmist, through the Spirit of Christ, is telling the Old Testament people to submit to God’s royal son. This Son is Christ, who will become the man Jesus is the New Testament. 

And in Proverbs we also read about the Son of God,

“Who but God goes up to heaven and comes back down? Who holds the wind in his fists? Who wraps up the oceans in his cloak? Who has created the whole wide world? What is his name—and his son’s name? Tell me if you know!” (Proverbs 30:4, NLT).

The Old Testament does refer to the Son of God. 

In the New Testament there are many places where Jesus is called the Son of God, and in each instance “Son of God” does not refer to the humanity of Jesus, “Son of God” refers to the deity of Jesus. When Jesus refers to Himself as a man He uses the phrase Son of Man, not Son of God. Son of God is the spiritual component of Jesus. Son of Man is the human element of the Son God. 

In other words, it was the Son of God who became human. It was the Son of God who entered the womb of Mary and took upon Himself flesh. God had become man. In this sense, the Word of God is synonymous, or the same as the Son of God. It is the same of the Christ, or Redeemer, or Messiah, or Anointed One – all names refer to the 2nd person of the Trinity. 

The Jewish people of Jesus’ time had no problem understanding that Jesus was saying that He was God when Jesus said, “My Father is always working, and so am I.” (John 5:17, NLT).  As soon as Jesus said that God was His Father, they were ready to kill him. Why? We read in the next verse that “the Jewish leaders tried all the harder to find a way to kill him (Jesus). For he not only broke the Sabbath, he called God his Father, thereby making himself equal with God.”

Later in John Jesus again says that God is His Father, and this time the Jews make it clear by saying that they want to kill Him because He is saying He is God, “The Father and I are one.”

31 Once again the people picked up stones to kill him. 32 Jesus said, “At my Father’s direction I have done many good works. For which one are you going to stone me?”

33 They replied, “We’re stoning you not for any good work, but for blasphemy! You, a mere man, claim to be God” (John 10:30-33).

When Jesus was arrested and was getting interrogated by the High Priest, Jesus referred to Himself as the Messiah, the Son of God. We read in Matthew, 

 “ Then the high priest said to him, “I demand in the name of the living God—tell us if you are the Messiah, the Son of God.”

64 Jesus replied, “You have said it. And in the future you will see the Son of Man seated in the place of power at God’s right hand[i] and coming on the clouds of heaven.”[j]

65 Then the high priest tore his clothing to show his horror and said, “Blasphemy! Why do we need other witnesses? You have all heard his blasphemy. 66 What is your verdict?”

“Guilty!” they shouted. “He deserves to die!”

67 Then they began to spit in Jesus’ face and beat him with their fists. And some slapped him, 68 jeering, “Prophesy to us, you Messiah! Who hit you that time?” (Matthew 26:63-67).

What about the demons. They were very aware that God was walking on earth in the body of a man. There were times when Jesus was confronting a demon that the demon would cry out to Jesus, you are the Son of God. In Luke 4:41we read, “Moreover, demons came out of many people, shouting, “You are the Son of God!” But he rebuked them and would not allow them to speak, because they knew he was the Messiah.”

It’s as if Jesus wanted people to figure out from themselves that He was God in the body of a man, that is maybe why Jesus would not let the demons speak and declare who He was. This is only a guess on my part. 

In another part of the New Testament, in Matthew we read about some more demons, it says (Matthew 8:29), “They began screaming at him, “Why are you interfering with us, Son of God?” The demons knew who Jesus was. He was God in the flesh, and they said Jesus was God by saying, Jesus is the Son of God. This is why in Islam the Qu’ran says that God does not have a son. The Qu’ran denies the trinity and the deity of Jesus. 

When Jesus was talking to Martha, Martha said to Him, John 11;27, ““Yes, Lord,” she replied, “I believe that you are the Messiah, the Son of God, who is to come into the world.” She knew that the Son of God was the eternal God, and that it was the eternal Son of God who had been sent into the world to die on the cross for our sins. 

This is also why we read in the letter of 1st John that if we have the Son we have life, because to have the Son means that we have the Spirit of God inside of us, because the Son of God is Spirit. We read in 1st John, “(1 John 5:12) “Whoever has the Son has life; whoever does not have the Son of God does not have life.”

And it also says in 1st John, (1 John 4:15),

“f anyone acknowledges that Jesus is the Son of God, God lives in them and they in God.”

The Jewish leaders got it wrong when they thought that Jesus was blaspheming when He said of Himself that He was the Son of God. The leaders said, John 19:7,  “We have a law, and according to that law he must die, because he claimed to be the Son of God.”