The opponents of eternal sonship may convince themselves that they have refuted it by offering several plausible reasons why Christ is called the Son of God before His incarnation which do not require that He is eternally generated by the Father. The problem with their argumentation is that it entirely forgets or neglects many related aspects of the biblical data. One such piece of data is the other name given to the Son of God before the creation of the world. According to John 1:1-3 before the creation of the world He is the Word of God.
John 1:1-3 In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things came into being through Him, and apart from Him nothing came into being that has come into being.
Notice several things about this famous and pivotal assertion of the Apostle of John. First, it clearly affirms the full deity of Christ. Not withstanding all the evasions of Jehovah’s Witnesses and others, the clear meaning of the third clause of verse 1 in this context is that the Word is as to His substance, nature, or being God.
Second, in the first two clauses of verse 1 two persons are distinguished. While in the third clause no definite article precedes God, the definite articles are used with the noun, Word, and the noun, God, in the first two clauses: So one person is “the Word” and the other person is called “the God.” This clearly means that “the Word” is the Word of “the God.” These names clearly suggest the derivative character of the person of “the Word” and the primacy of the person called “the God” in this context. To put this in more familiar terms, the Son is described as the eternal Word of the Father.
Third, an intimate personal relationship is ascribed to the two persons in the second clause of verse one. The Greek preposition pros is used in the clause that is translated “and the Word was with God.” Pros has for its root meaning, toward. Thus, it might be translated and “the Word was toward the God.” This already suggests the idea of a personal relationship. We are not, therefore, surprised to find that the use of pros with the accusative (which is what we have here) has for one of its uses (according to the Greek lexicon) the “denoting of a friendly relationship.” “The Word” was oriented toward “the God” in a loving personal relationship.
Fourth, the Word is, then, associated with the Father in the work of creation. The Bible begins with the words: “In the beginning God created the heavens and the earth.” John, thus, affirms that at that period in the beginning—at the creation of the world—“He was in the beginning with God.” Verse 3, therefore, goes on to assert that the Father created the world (everything that was created) through the Son: “All things came into being through Him, and apart from Him nothing came into being that has come into being.” This clearly implies two things. First, it affirms that the Son is Himself not created, because everything that came into being came into being through Him. Second, it affirms that He was the subordinate means of creation. The Father made all things, but He made all things “through” His Son. John is thinking of the statement of in Genesis 1:3, “And God said.” God created the world through His Word and that Word has become incarnate in Jesus Christ. The preposition, dia, used here denotes means, agency, or instrumentality. The Son was the instrument or means or agent though which the Father made the world. His eternal, subordinate, personal relationship to the Father as His Word comes to expression in the work of creation as He is the subordinate means of creation.
The eternal Wordship of Christ plainly implies His eternal Sonship and the role of eternal, personal subordination to the will of the Father that He gladly fulfills.