**Nobody claims to comprehend it all, but we believe there is only one, true God and He is manifested to mankind through the Father, the Son and the Holy Spirit.**
And Jesus Christ claims that the Son and the Holy Ghost have a common original source: God the Father.
That’s why you find phrases like ‘Son of God’, and ‘Spirit of God’ in the scriptures. ‘God the Son’, and ‘God the Holy Spirit’, are not found in the scriptures because they do not properly define God.
Like I asked you before,
How many Gods do you believe exist? If Jesus is called “God” and the Holy Spirit is called “God” and the Father is called “God”, do we have three Gods (like the Muslims claim Christians do) or ONE God manifest as three “persons”?
Don't get hung up on terms like "God the Son" versus "Son of God". In the Scriptures the titles are interchangeable and Jesus IS "God with us" which is why He can be called God the Son. We don't have three Gods but only ONE God manifested in three persons, Father, Son and Holy Spirit. The Father is God, the Son is God and the Holy Spirit is God. Don't forget that the Son has always existed as has the Father and the Holy Spirit. Jesus took on human flesh at the incarnation (what the word actually means) - a specific space and time - but has always existed as the Son of God.
Instead of trying to comprehend how all this is possible with our mortal, finite minds, we accept by faith what God has revealed about Himself to us through His word. The early church, faced with heresy from the start from those who denied the divinity of Jesus Christ, wrote up a creed and defined the best they could, using the Scriptures as their guide, the doctrine of the Trinity. Is it perfect? Is it comprehensive? Is it everything that could be said about the Trinity? Maybe not, but everything it says is proved by Scripture.
Jesus never said we have to understand everything about the Trinity to be saved, but He did say if we deny He is come in the flesh, is the I AM, is the incarnate God who is able to make full atonement for our sins by His precious, sinless blood, we would die in our sins. That is why I accept that He is God even though I don't fully understand everything that entails. It IS faith, after all, and one day we will know as we are known. We will have the mind of Christ and it will ALL make perfect sense.