Since the Father is God, and the Son is God, how are there not two Gods?
We begin answering this by noting that scripture is clear on the point that there is only one God, and that it is equally clear that this one God is the person of the Father in particular. This is seen explicitly from scripture:
“There is one body and one Spirit, just as also you were called in one hope of your calling; 5 one Lord, one faith, one baptism, 6 one God and Father of all who is over all and through all and in all.” (Ephesians 4:4-5 NAS)
“This is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent.” (John 17:3 NAS)
“yet for us there is but one God, the Father, from whom are all things and we exist for Him; and one Lord, Jesus Christ, by whom are all things, and we exist through Him.” (1 Corinthians 8:6 NAS)
But even once it is understood that the Father is the one God of the Christian faith, the question still remains, how does the Son, Who is also God, not by His divinity destroy monotheism?
In our last installment of this series, we examined the first part of the answer to this question, namely, that the Father is the one and only God because the Father alone is the uncaused Cause of all. The Father through the Son created all things; but even the Son and Holy Spirit, we observed, have the Father as their atemporal origin and source, the Son being of the Father by eternal generation, and the Holy Spirit being of the Father by eternal procession. This means that the Father alone is entirely uncaused and unoriginate; no greater source or reason for His being can be pointed to than Himself. He simply is always all that He is, uncaused, unbegotten.
Since then, there is only one uncaused Cause, and this is the Father, we see why scripture styles God the Father in particular the one God, and why, since the Son and Holy Spirit are not also uncaused, they do not constitute second and third Gods.
Today we examine a second part of the answer to our question, related to the last, that just as the Father alone is the “one God” because He alone is the uncaused Cause of all, so also the Father alone is the Supreme Authority, the Head without a head, meaning, that He is the authoritative head over all, even over His own Son and Spirit, and there is none who has headship over Him; there is no higher authority than the one God, the Father.
We see God’s headship over His Son and Spirit in the following passages:
“But I want you to know that the head of every man is Christ, the head of woman is man, and the head of Christ is God.” (1 Corinthians 11:3 NKJV)
15 So the Lord sent a pestilence upon Israel from the morning until the appointed time, and seventy thousand men of the people from Dan to Beersheba died. 16 When the angel stretched out his hand toward Jerusalem to destroy it, the Lord relented from the calamity and said to the angel who destroyed the people, “It is enough! Now relax your hand!” And the angel of the Lord was by the threshing floor of Araunah the Jebusite. (2 Samuel 24:15-16 NASB)
“Jesus said to her, “Do not cling to Me, for I have not yet ascended to My Father; but go to My brethren and say to them, ‘I am ascending to My Father and your Father, and to My God and your God.’”” (John 20:17 NKJV)
“Blessed be the God and Father of our Lord Jesus Christ, who according to His abundant mercy has begotten us again to a living hope through the resurrection of Jesus Christ from the dead,” (1 Peter 1:3 NKJV)
“To Him who loved us and washed us from our sins in His own blood, 6 and has made us kings and priests to His God and Father, to Him be glory and dominion forever and ever. Amen.” (Revelation 1:5b-6 NKJV)
“that you may with one mind and one mouth glorify the God and Father of our Lord Jesus Christ.” (Romans 15:6 NKJV)
“Do you not believe that I am in the Father, and the Father in Me? The words that I speak to you I do not speak on My own authority; but the Father who dwells in Me does the works.” (John 14:10 NKJV)
“And I will pray the Father, and He will give you another Helper, that He may abide with you forever— 17 the Spirit of truth, whom the world cannot receive, because it neither sees Him nor knows Him; but you know Him, for He dwells with you and will be in you.” (John 14:16-17 NKJV)
“But the Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all things that I said to you.” (John 14:26 NKJV)
In these passages we see that there is no higher authority over God the Father, and that He is Supreme:
“For when God made a promise to Abraham, because He could swear by no one greater, He swore by Himself, 14 saying, “Surely blessing I will bless you, and multiplying I will multiply you.” 15 And so, after he had patiently endured, he obtained the promise. 16 For men indeed swear by the greater, and an oath for confirmation is for them an end of all dispute.” (Hebrews 6:13-18 NKJV)
“Then comes the end, when He delivers the kingdom to God the Father, when He puts an end to all rule and all authority and power. 25 For He must reign till He has put all enemies under His feet. 26 The last enemy that will be destroyed is death. 27 For “He has put all things under His feet.” But when He says “all things are put under Him,” it is evident that He who put all things under Him is excepted. 28 Now when all things are made subject to Him, then the Son Himself will also be subject to Him who put all things under Him, that God may be all in all.” (1 Corinthians 15:24-28 NKJV)
From these passages we see that the Son and Spirit are subordinate to the Father as Their Head, and that the Father has headship over not only all creation, but also over His Son and Spirit. We also see that the Father Himself is the greatest authority, having no higher authority above Him; the Father alone is the Supreme Authority. On this account then, as well as the fact that the Father alone is the uncaused Cause of all, scripture styles the person of the Father the “one God”. And since the Son and Holy Spirit do not also have absolute supreme authority equal with the Father, They do not constitute second and third Gods, but the Father alone being the Supreme Authority over all is the one God.
Having seen this shown from scripture, let us now examine the testimonies of some of the ancient fathers of the church on this same point:
Novation of Rome
“Moreover, the Son does nothing of His own will, nor does anything of His own determination; nor does He come from Himself, but obeys all His Father’s commands and precepts; so that, although birth proves Him to be a Son, yet obedience even to death declares Him the minister of the will of His Father, of whom He is. Thus making Himself obedient to His Father in all things, although He also is God, yet He shows the one God the Father by His obedience, from whom also He drew His beginning.” (On the Trinity, Chapter 31)
“For all things being subjected to Him as the Son by the Father, while He Himself, with those things which are subjected to Him, is subjected to His Father, He is indeed proved to be Son of His Father; but He is found to be both Lord and God of all else. Whence, while all things put under Him are delivered to Him who is God, and all things are subjected to Him, the Son refers all that He has received to the Father, remits again to the Father the whole authority of His divinity. The true and eternal Father is manifested as the one God, from whom alone this power of divinity is sent forth, and also given and directed upon the Son, and is again returned by the communion of substance to the Father. God indeed is shown as the Son, to whom the divinity is beheld to be given and extended. And still, nevertheless, the Father is proved to be one God; while by degrees in reciprocal transfer that majesty and divinity are again returned and reflected as sent by the Son Himself to the Father, who had given them; so that reasonably God the Father is God of all, and the source also of His Son Himself whom He begot as Lord. Moreover, the Son is God of all else, because God the Father put before all Him whom He begot. Thus the Mediator of God and men, Christ Jesus, having the power of every creature subjected to Him by His own Father, inasmuch as He is God; with every creature subdued to Him, found at one with His Father God, has, by abiding in that condition that He moreover was heard, briefly proved God His Father to be one and only and true God.” (On the Trinity, Chapter 31)
“But are you afraid, man, lest, having confessed that there are two hypostases, you introduce two sources and cast aside the monarchical divinity? Well then, learn that because there is one God who is without source and unbegotten, but the Son has been begotten from him, there will be one source and a single monarchy and kingship, since even the Son himself acknowledges his Father as source. “The head of Christ is God,” according to the Apostle. But are you anxious that one might have to accept that there are two gods if you confess that there are two hypostases of Father and Son? But know this too: that the man who grants that there are two hypostases of Father and Son is not compelled to say there are two Fathers, nor that there are two Sons, but will grant that one is the Father and the other is the Son. Thus, in the same way, it is not necessary for the man who posits two hypostases to grant that there are two gods. For we neither deem them equally worthy of honor, nor both without source and unbegotten, but deem the one [hypostasis] as unbegotten and without source, while [we deem] the other as begotten and having the Father as his source. For this reason, even the Son himself teaches that his Father is also his God, when he says, “I go to my Father and to your Father and to my God and to your God.” Thus God is shown to be both Father and God of the Son himself. For this reason then, the God of the Son is proclaimed by the Church to be one. And the Son, when he is compared to the Father, will not also be God of the Father himself, but only-begotten Son, his “beloved,” “image of the invisible God,” and “radiance” of the paternal glory; and he reveres, worships, and glorifies his own Father, acknowledging him as God even of himself, to whom he has been reported also to pray, to whom he gives thanks, and to whom he also became “obedient unto death.” And he confesses that he lives “because of the Father” and is able to do nothing without the Father and that he does not do his own will but the will of the Father. Indeed, he explicitly says, “I have come down from heaven not to do my own will but the will of him who sent me.”” (On Ecclesiastical Theology, Book 2, Ch 7)
“Believing then in the All-perfect Triad, the most Holy, that is, in the Father, and the Son, and the Holy Ghost, and calling the Father God, and the Son God, yet we confess in them, not two Gods, but one dignity of Godhead, and one exact harmony of dominion, the Father alone being Head over the whole universe wholly, and over the Son Himself, and the Son subordinated to the Father; but, excepting Him, ruling over all things after Him which through Himself have come to be, and granting the grace of the Holy Ghost unsparingly to the saints at the Father’s will. For that such is the account of the Divine Monarchy towards Christ, the sacred oracles have delivered to us.”
Council of Sirmium
“XVII. If any man says that the Lord and the Lord, the Father and the Son, are two Gods because of the aforesaid words: let him be anathema. For we do not make the Son the equal or peer of the Father, but understand the Son to be subject. For He did not come down to Sodom without the Father’s will, nor rain from Himself but from the Lord, to wit, by the Father’s authority; nor does He sit at the Father’s right hand by His own authority, but because He hears the Father saying, Sit on My right hand. (Council of Sirmium against Photinius)
“And now have you not perceived, my friends, that one of the three, who is both God and Lord, and ministers to Him who is in the heavens, is Lord of the two angels? For when [the angels] proceeded to Sodom, He remained behind, and communed with Abraham in the words recorded by Moses; and when He departed after the conversation, Abraham went back to his place. And when he came [to Sodom], the two angels no longer conversed with Lot, but Himself, as the Scripture makes evident; and He is the Lord who received commission from the Lord who [remains] in the heavens, i.e., the Maker of all things, to inflict upon Sodom and Gomorrha the [judgments] which the Scripture describes in these terms: ‘The Lord rained down upon Sodom and Gomorrha sulphur and fire from the Lord out of heaven.”” (Dialogue With Trypho, Chapter 56)
“It is again written by Moses, my brethren, that He who is called God and appeared to the patriarchs is called both Angel and Lord, in order that from this you may understand Him to be minister to the Father of all things, as you have already admitted, and may remain firm, persuaded by additional arguments.” (Dialogue With Trypho, Chapter 58)
“I shall give you another testimony, my friends, from the Scriptures, that God begot before all creatures a Beginning, [who was] a certain rational power [proceeding] from Himself, who is called by the Holy Spirit, now the Glory of the Lord, now the Son, again Wisdom, again an Angel, then God, and then Lord and Logos; and on another occasion He calls Himself Captain, when He appeared in human form to Joshua the son of Nave (Nun). For He can be called by all those names, since He ministers to the Father’s will…” (Dialogue With Trypho, Chapter 61)
Quotes from Eusebius taken from: Eusebius Pamphilius, On Ecclesiastical Theology, trans. Kelly McCarthy Sproerl and Markus Vinzent (Washington, D.C.: The Catholic University of America Press, 2017).