John 1:18. No man hath seen God at any time; the only begotten Son, which is in the bosom of the Father, He hath declared Him.
Jesus, the Word, is the declaration of His Father, the Unseen God. He has declared the nature of God in His teachings, and throughout scripture.
In Greek, the word for God is Theon. There is no article, such as “the God.” The lack of an article indicates that John is presenting God in His nature of being rather than as a person. ‘Deity’ might be a more accurate translation. The meaning is that no human being has ever seen the essence of Deity.
This explanation is helpful to me. It is almost impossible for me to wrap my mind around His pre-existence, Self-existence, endless existence; the Alpha and Omega, the Beginning and the End. In my finite mind, I need tangibles. If I think too long about the fact of His ALWAYS existing, having no beginning and no ending. I get a little dizzy 🙂 This is a good place for Hebrews 11:1. “Now, faith is the substance of things hoped for; the evidence of things unseen.” We certainly have limitless evidence of the existence of God all around us every day.
The testimony of Jesus Christ is the most reliable witness we have of the existence of God. The Son has made known the Father. The Son and the Father are one: In John 10:30, Jesus made that simple and profound statement. “I and My Father are One.”