Ask any Christian, "What is the single most important teaching in the Bible?" He should be able to answer, "That God is One."
This is in fact the answer that Jesus Christ Himself gave. A man asked Him, "What is the most important commandment of all?"
Jesus began, "The First is, `Hear, O Israel: The Lord our God, the Lord is One...'" (Mark 12: 20-32) The Jew who asked this was not at all surprised by the answer. He knew that this commandment about loving the One Lord was to be written on their hearts, taught to their children, and discussed at home and while travelling, morning and evening. (Deuteronomy 6: 4-7) He knew also that the first of the Ten Commandments was to "have no other gods." (Exodus 20:3)
Again and again the Bible emphasizes the oneness of God. "Thou art God, and Thou alone." (2 Kings 19:15) "There is no God with Me." (Deuteronomy 22:39) "I am Jehovah (Yahweh) and there is none else." (Isaiah 45:5) My glory will I not give to another." (Isaiah 42:8, 48:11) It is very clear that the Unity of God must be central to all our thought about Him.
It might seem that the birth, life, and resurrection of Jesus Christ presents a challenge to this. Did the One God Himself come to earth? Or was Jesus someone else? Some Christians have accepted the idea that the One God is made up of Three equal and eternal Persons. Others have said that Jesus is not God, but the Son of God, or just "a child of God" like everyone else.
We can understand better who Jesus is, by comparing the things that are said of Jesus with the things that are said of the One God, Jehovah. The table below summarizes some of the passages which indicate that Jehovah and Jesus are the same Divine Person.
The coming of the Messiah had been foretold for ages. Most Christians are quite familiar with prophecies such as, "Behold a virgin shall conceive and bear a Son." It is interesting that so many of these prophecies tell that God Himself--the One Lord, Jehovah--would come on earth to be with His people. For example, the passage just quoted goes on to say, "His name shall be called God-With-Us." (Isaiah 7:14) Another passage declares that the Child who would be born would be "the Mighty God, the Everlasting Father." (Isaiah 9:6) And when John the Baptist was announcing the coming of Jesus, he quoted the prophecy which says, "Prepare the way of Jehovah; make straight in the desert a highway for our God." This passage continues, "The glory of Jehovah shall be revealed... Say to the cities of Judah, `Behold your God!' Behold the Lord Jehovah shall come." (Isaiah 40:3,5,10; Luke 3:4) People prayed for the coming of the One God: "Bow Your heavens, Jehovah, and come down." (Psalm 144:5) His coming is the source of our joy: "And it shall be said in that day, `This is our God. We have waited for Him that He may deliver us; this is Jehovah... We will rejoice and be glad in His salvation.'" (Isaiah 25:9) So of course, it should be--it must be--that the One God would want to be with His people: "`Behold, I am coming and I will dwell in your midst,' says Jehovah." (Zechariah 2:10)
These prophecies were fulfilled when Jesus Christ was born. In Jesus Christ, the One God had come to manifest Himself to mankind and dwell with them. Consequently, there are many passages in the New Testament which identify Jesus as that One God. He is called the True God, (1 John 5:20) Savior, (Luke 2:11; Matthew 1:21) God With Us. (Matthew 1:23) The Wise Men knew the prophecies, so they recognized Jesus as their King and God: they came and worshipped Him. (Matthew 2:2, 11) And all the angels worshipped Him at His birth. (Hebrews 1:6) Jesus identified Himself as the One God when He spoke of Himself as the One who came down from heaven to give life to the world, (John 6:33, 38) and when He said "He who has seen Me has seen the Father," (John 14:9.) and "I and My Father are One." (John 10:30)
Although these many passages show that Jesus and Jehovah are One Divine Person there are other passages which show a distinction between the Father and the Son. We cannot come to a complete understanding of the Bible or of God by looking at only one set of passages. Instead, we need some way of reconciling all the teachings.
It may help us integrate the various teachings to keep in mind the fact that Jesus changed between the time of His birth and His resurrection. During His life on earth Jesus was tempted. (Luke 4:1-13) He was not yet glorified, (John 12:28) But had to enter into His glory (Luke 24:26) by degrees. (John 7:39) He "increased in wisdom and stature." (Luke 2:52) Before the resurrection, the union of Jehovah and Jesus was not yet complete, so Jesus said, "I am going to My Father, for My Father is greater than I." (John 14:28; 16:16) It was only after this work was finished (John 19:30) that He could say, "All power has been given to Me in heaven and earth." (Matthew 28:18) It was not till then that He was completely and fully God.
This explains why Jesus was so often called the "Son of God." Jesus had come forth from God, and God was gradually manifesting Himself in Jesus. So at first, Jesus was the Son of God, and later became One with Jehovah and fully Divine.
Generally, the passages which distinguish between Father and Son do not describe the kind of relationship that would exist between two Persons. It is more like the kind of relationship that exists between Soul and Body. For example, Jesus said, "The words that I speak unto you I speak not of Myself: but the Father who dwells in Me does the works." (John 14:10) We don't speak of one person dwelling in another person, but it does make sense to think of the soul dwelling within the body, or in this case, of the infinite Divine Soul dwelling within Jesus Christ. So Christ is called the "image of the invisible God" (Colossians 1:15; 2 Cor 4:4) and "the form of God." (Philemon 2:6) As Paul said, we see "the glory of God in the face of Jesus Christ," (2 Corinthians 4:6) and "in Him dwells all the fullness of the Godhead bodily." (Colossians 2:9)
Other passages describe a similar relationship. John said, "No one has seen God at any time. The only-begotten Son, who is in the bosom of the Father, He has revealed Him." (John 1:18) The Divine Soul is invisible (like a human soul). "You have neither heard His voice at any time, nor seen His form." (John 5:37; 6:46) But in Jesus, that Soul is revealed, as in Its own Body. Since you communicate with a person's soul only by means of his body, Jesus said, "No one comes to the Father but by Me." (John 14:6) And by coming to Jesus Christ we can draw near to the One God of the universe Who has come to earth to show Himself to us in His own loving and gentle Human Form.