“‘Son of God’ is merely a metaphorical expression in the Bible, just as other righteous people are called ‘sons of God.’ It is not a dogma, but an honorary title for Jesus as a prophet.”
It is true that in the Old Testament, “sons of God” is sometimes used metaphorically for angels (Job 1:6) or for Israel (Hos 11:1). But the New Testament designation of Jesus as “Son of God” is fundamentally different: it does not only mean closeness to God, but equality of divine essence.
Jesus himself uses the address “my Father” in a unique way. While he teaches his disciples to pray “Our Father” (Mt 6:9), he distinguishes himself from them: “My Father and your Father” (John 20:17). Thus, he claims an exclusive, eternal sonship. When he said, “My Father is working until now, and I am working” (John 5:17), the Jews immediately understood the claim: “For this reason the Jews were seeking all the more to kill him, because he was calling God his own Father, making himself equal with God” (John 5:18).
Numerous passages confirm this: Peter confesses Jesus as “the Son of the living God” (Mt 16:16), and Jesus affirms this confession as a revelation from the Father. At the baptism (Mt 3:17) and the transfiguration (Mt 17:5), the voice of the Father himself testifies: “This is my beloved Son.” Thomas exclaims: “My Lord and my God!” (John 20:28). Paul calls him “God’s own Son,” who “was not spared” (Rom 8:32), thus distinguishing him from all other creatures.
The Church understood from the beginning that this is an ontological, not merely metaphorical sonship. Ignatius of Antioch speaks of “Jesus Christ, our God” (Letter to the Romans Proemium, around 107). Irenaeus of Lyon emphasizes: “The only-begotten Son, the Word of God, is our Lord and God and Savior and King” (Adv. haer. III,19,1).
The dogma of the true Sonship of God was affirmed at the Council of Nicaea (325): Jesus Christ is “begotten, not made, consubstantial with the Father.” If “Son of God” had only been a metaphor, this theological struggle would have been unnecessary.
Counterargument from the Other Side
“In the Old Testament, many are called ‘sons of God’—so Jesus is not unique.”
Brief Refutation:
Yes, there are metaphorical applications. But in the case of Jesus, it is about the only-begotten sonship (monogenes, John 1:18), not a general sonship. He is not “one among many,” but the one through whom all others can become children of God (John 1:12).