Of course Jesus is eternal God. And has always been eternal God. And is the Word-and the Word was God (John 1:1-4). That's not the question. The question is how did Jesus come to have the name or title of "Son of God". No, it has nothing to do with His earthly birth to the virgin Mary. According to the Scriptures I posted, which you are responding to, but have conveniently ignored-Jesus was declared to be the Son of God THROUGH THE RESURRECTION OF THE DEAD (Romans 1:4). That's what God's Word the Bible says. And, as we continue to search the Scriptures we do find that Jesus is said to be the firstborn of all creation (Colossians 1:14,15) and the firstborn from the dead (Colossians 1:18). We're also told that He is the firstbegotten from the dead (Revelation 1:5). This is why God said, as Jesus came up out of the water (the water typifying hell, or the grave), "This is my beloved Son, in whom I am well pleased (Matthew 3:17b)". The picture is unmistakable. Jesus is baptized by John (pictured being baptized into His death at the foundation of the world) and then rises up out of the water/baptism of death-to be declared by God the Father, "This is My beloved Son...". Those granted eyes to see can see the beautiful harmony of the Scriptures as the baptism of Jesus fits in perfectly with Romans 1:4's declaration "declared to be the Son of God ...through the resurrection of the dead."
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https://www.facebook.com/groups/EBFSundayopenQandA/