The Arians had it right all along...if man’s smarts could approach the unfathomable mystery of God. But man has a pathetic, darkened intellect with which to try to see truth, and a weakened will with which to love God and do His will.
“Trust in the Lord with all thine heart; and lean not unto thine own understanding. In all thy ways acknowledge him, and he shall direct thy paths.” Proverbs 3:5-6
The relationship between God and Christ is only a mystery because the various creeds define it that way Believe in Christianity does not require belief in the Creeds. The Creeds were made by uninspired men.