There must be an ulimate, final authority. There has to exist a person or place beyond which there can be no higher source. There has to be a person or place in whom resides inherent authority. That ultimate authority is the source of all authority.
Bernard Ramm, in his book Pattern of Authority, suggests two sources of authority: superior position and truth. He refers to them as "Imperial" and "Veracious" authority. Applying these criteria to God show Him as the source of authority. "He (God - GT) alone is self-existent and supreme, who is what He is of His own right. If God exists, He is the ultimate criterion and power of truth and reality. All truth inheres in Him and issues from Him. The problem of authority thus becomes one with the proof and definition of God" (I.S.B.E., Vol. I, p. 334).
That God is ultimate authority is seen in His divine being. He has inherent authority because He is God (1 Cor. 15:24-28).
The divine names for God indicate His primary authority (Psa. 96:8): El Elyon - God most high (Gen. 4:18); El Shaddai - God Almighty (Ex. 6:3); Yahweh (Jehovah), His memorial name (Hos. 12:5-6). "Jehovah" means "Self-Existent or Eternal" (Strong's Hebrew-Chaldee Dictionary, p. 47). It is related to the designation "I am" (Ex. 3:14). It is significant that Jesus said of Himself, "Before Abraham was, I am" (John 8:58), thus showing His divinity, His right to command.
The authority of God is rooted in His inherent nature and character: His eternal existence (Deut. 33:27); omniscience -- limitless wisdom and knowledge (1 Sam. 2:3; 1 John 3:20); omnipotence -- matchless power and strength (Rev. 19:6; Heb. 11:3); and perfect holiness and righteousness (1 Pet. 1:16; Titus 1:2).
God is the ultimate authority by reason of the fact that He is both creator and sustainer of the entire universe (Gen. 1:1; Acts 17:24-29). All things were created by Him and for Him and by Him all things consist (Col. 1:16-17).
God alone has the inherent right to command. The only kind of authority mankind has is delegated authority. No human has either the right or power to assume to be on an equality with God (Isa. 55:8-9). Delegated authority is restricted by stipulated purpose or intent.
Earthly governments receive their right to make and enforce civil law from God (Rom. 13:1).
The right to enact religious law does not reside in man. It never has and never will. Man cannot set forth his own ideas and opinions as the standard for others to follow. Even the apostles were never anything more than inspired messengers sent to deliver a divine message. For them to have taught or commanded anything other than that which heaven had revealed to them would have caused them to be accursed (Gal. 1:6-9).