There are several questions that are part of this lead question. Was Jesus always the Son of God? Doesn’t “sonship” imply inferiority to God the Father? Was there a point in time, such as Jesus’ baptism or His resurrection, when He became or was designated the Son of God? Doesn’t being a “son” imply that He was, therefore, a created being?
In answering these questions, several basic theological facts must be observed and the scriptures underlying them. When these facts are seen, then greater clarity comes to us in answering the above questions.
(1) The Bible teaches the eternality of Christ.
The term “eternality” means that Christ (the 2nd Person of the Godhead) always existed. So He not only existed before creation, but He always existed. Eternality is one of the many attributes of God, and since Jesus possessed these attributes, He is deity. In Colossians 2:9, the Apostle Paul clearly and succinctly states that “in Him (Christ) all the fullness (Gr. pleroma) of deity dwells in bodily form”. Everything that makes God to be God is found, without exception, in the Person of Christ. Many other scriptures declare this same truth. For example, John 1:1 plainly states that Christ is God (thus possessing all God’s attributes); Isaiah 9:6 declares the Son is the eternal Father of His people, Israel; and Hebrews 1:3 says that Christ, the Son, is the exact, perfect representation of the nature of God. And furthermore, not only are all the attributes of God present in the Son (the 2nd Person), but the various names of God are ascribed to Him (e.g., Adonai in Psalm 110) as well as plain declarations of His deity are found in numerous places (e.g., Heb. 1:8; John 1:1; Titus 2:13). All of these, and other scriptures, point without hesitation to the fact that Christ was/is fully God and is, therefore, eternal.
(2) The Bible teaches that Jesus was the “Son” eternally.
Christ has been a Son from eternity. He is represented as already the Son of God and was sent into to the world as such (John 3:16-17; Gal. 4:4). According to Psalm 2:7, Christ is declared to be the Son of God and begotten in the eternal decree of God. The decree of God is from eternity past which means that the Son is declared the begotten Son from eternity past. Psalm 2:7 is quoted three times in the N.T. (Acts 13:33; Heb. 1:5; 5:5) and point to the unique status of Christ and confirm His eternal sonship.
We need to admit the obvious, that our minds cannot really, fully comprehend the idea of eternity. We can imagine what future eternity is like in that it goes on and on forever. But thinking about going back into eternity but not being able to come to a point of origin baffles us. It is from “eternity past” that the decree of God existed and the sonship of Christ. The term “begotten” as we normally think of it suggests a beginning of some kind. When a child is begotten, that child did not exist before that moment. And while that is the usual way of thinking about “begotten,” that is not the emphasis of the scriptures. In relationship to Christ the term (as in Col. 1:15 and Psalm 2:7) is emphasizing His rank and position. He has priority over all of creation. It does not mean, as the Jehovah’s Witnesses say, that He was the first one created.
When the Bible speaks of God, it very often uses terms that we can relate to. For example, God’s hand is on this person or situation, or God’s eye is over all the earth. To our knowledge, God has neither, but using human terminology, it is an attempt to tell us things about God. That the Son is begotten is simply letting us know what John 1:1 is stating, and that is that Christ is distinct from the Father (as is the Holy Spirit) and sustains a relationship of unity. Christ is fully God, but He is not the same as the Father. The Word (Christ) is said to be God, and yet He is “with” God. There is no idea of inferiority (because the fullness of deity resides in Him), nor of beginning (He has eternally existed in the same way as the Father has eternally existed). In the thinking of the Jews, “son of” did not usually imply being subordinate, but rather that of equality and identity of nature, whether Christ was called “son of God” or “son of man.” This understanding is clearly behind the murderous intentions of the Jews in John 5:16-27. The claims being made by Jesus were “off the chart” in the thinking of the Jewish leadership; He was claiming to be equal with Jehovah God. An audacious claim if it wasn’t true.
(3) The Bible verses that sometimes are used to teach He became the “son” at some point in time do not really teach that.
Over the centuries, some have proposed that Christ became the “Son” at some particular event in time. It has been suggested that He became the Son of God at the incarnation, at His baptism, at His resurrection or at His ascension back into heaven. As we have noted, there are many scriptures which state that Christ was the Son eternally. A close, careful investigation of the texts of scripture, including the numerous passages mentioned in this brief study (as well as many others), causes us to see that the verses presented as evidence are not really saying that He became the Son at some point in time. One example will have to suffice. In the Revised Standard Version of Romans 1:4, it says that Christ was “designated Son of God in power according to the Spirit of holiness by his resurrection from the dead, Jesus Christ our Lord.” The point Paul is making is that His resurrection authenticated to men both His deity and His Sonship. These didn’t become true at His resurrection, they were validated by His resurrection. The resurrection was a factual revelation of who He is and was. It authenticated all of His claims, and all the statements made about Him in Moses, the Psalms and the Prophets.
So, we conclude that the consistent testimony of the OT writers as well as the NT apostles, is that Christ is deity, which means He has all of the attributes of God which includes eternality. We also conclude that the “Son” does not suggest a beginning nor does it imply inferiority. Our use of the term is not at all identical with the scriptural use of the term. Christ is fully deity but He is not the Father. His “sonship” has been their relationship from eternity, included in the eternal decree of God.