How can Jesus be the Son of God and God at the same time?
The concept is that God is the beginning and the end. He created all things and nothing existed before him. "The Son, the Father, and the Holy Ghost" Brings all three together as say the Holy Ghost and all things existing are one.
The doctrine of the Trinity -- that God the Father, God the Son, and God the Holy Spirit are each equally and eternally the one true God -- is admittedly difficult to comprehend, and yet is the very foundation of Christian truth. Although skeptics may ridicule it as a mathematical impossibility, it is nevertheless a basic doctrine of Scripture as well as profoundly realistic in both universal experience and in the scientific understanding of the cosmos.
Both Old and New Testaments teach the Unity and the Trinity of the Godhead. The idea that there is only one God, who created all things, is repeatedly emphasized in such Scriptures as Isaiah 45:18:
"For thus saith the Lord that created the heavens; God himself that formed the earth and made it; I am the Lord; and there is none else."
A New Testament example is James 2:19:
"Thou believest that there is one God; thou doest well; the devils also believe, and tremble."
The three persons of the Godhead are, at the same time, noted in such Scriptures as Isaiah 48:16:
"I have not spoken in secret from the beginning; From the time that it was, there am I; and now the Lord God, and his Spirit, hath sent me."
The speaker in this verse is obviously God, and yet He says He has been sent both by The Lord God (that is, the Father) and by His Spirit (that is, the Holy Spirit).
The New Testament doctrine of the Trinity is evident in such a verse as John 15:26, where the Lord Jesus said:
"But when the Comforter is come whom I will send unto you from the Father, He shall testify of me."
Then there is the baptismal formula:
"baptizing them in the name of the Father, and of the Son, and of the Holy Ghost" (Matthew 28:19).
One name (God) -- yet three names!
Jesus -- That Jesus, as the only-begotten Son of God, actually claimed to be God, equal with the Father, is clear from numerous Scriptures. For example, He said:
"I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty" (Revelation 1:8).
Holy Spirit -- Some cults falsely teach that the Holy Spirit is an impersonal divine influence of some kind, but the Bible teaches that He is a real person, just as are the Father and the Son. Jesus said:
"Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak; and he will show you things to come" (John 16:13).
Tri-unity -- The teaching of the Bible concerning the Trinity might be summarized thus. God is a Tri-unity, with each Person of the Godhead equally and fully and eternally God. Each is necessary, and each is distinct, and yet all are one. The three Persons appear in a logical, causal order. The Father is the unseen, omnipresent Source of all being, revealed in and by the Son, experienced in and by the Holy Spirit. The Son proceeds from the Father, and the Spirit from the Son. With reference to God's creation, the Father is the Thought behind it, the Son is the Word calling it forth, and the Spirit is the Deed making it a reality.
We "see" God and His great salvation in the Son of God, the Lord Jesus Christ, then "experience" their reality by faith, through the indwelling presence of His Holy Spirit.
Though these relationships seem paradoxical, and to some completely impossible, they are profoundly realistic, and their truth is ingrained deep in man's nature. Thus, men have always sensed first the truth that God must be "out there," everywhere present and the First Cause of all things, but they have corrupted this intuitive knowledge of the Father into pantheism and ultimately into naturalism.
Similarly, men have always felt the need to "see" God in terms of their own experience and understanding, but this knowledge that God must reveal Himself has been distorted into polytheism and idolatry. Men have thus continually erected "models" of God, sometimes in the form of graven images, sometimes even in the form of philosophical systems purporting to represent ultimate reality.
Finally, men have always known that they should be able to have communion with their Creator and to experience His presence "within." But this deep intuition of the Holy Spirit has been corrupted into various forms of false mysticism and fanaticism, and even into spiritism and demonism. Thus, the truth of God's tri-unity is ingrained in man's very nature, but he has often distorted it and substituted a false god in its place.
Recommended book, The Bible Has the Answer
Authors: Henry Morris and Martin Clark (excerpted from The Bible Has the Answer by Morris and Clark, published by Master Books, 1987).