This page contains a quote from Edmund J. Fortman’s book, The Triune God, p 66-70: This is also available from Internet Archive:
“THE COUNCIL OF NICEA
In 325 a Council was convoked by Constantine the emperor at Nicea in Bithynia. The names of over 220 of those in attendance known. Most of these came from the East. Five or six came from the West, among these Hosius of Cordova and the priests Vitus and Vincent, who represented Pope Sylvester.
There is no record of the acts of the Council. Only its Creed, 20 canons, and a synodal letter condemning Arius are extant (Denz 125-130).
The Nicene Creed says simply:
We believe in one God,
the Father almighty,
creator of all things both visible and invisible.
And in one Lord Jesus Christ,
the Son of God,
the only-begotten born of the Father,
that is, of the substance of the Father;
God from God, light from light, true God from true God;
begotten, not created,
consubstantial with the Father;
through Him all things were made,
those in heaven and those on earth as well….
And we believe in the Holy Spirit.
As for those who say:
‘There was a time when He did not exist’ and
‘before He was begotten, He did not exist’ and
‘He was made from nothing, or from another hypostasis or essence,’
alleging that the Son of God is mutable or subject to change
such persons the Catholic and apostolic Church condemns (Denz 125-126).
What the Creed rejected is clear enough. It was Arius’ doctrine that the Son is not true God but a creature, that He was not begotten of the substance of the Father but was made from nothing, that He was not eternal but rather that ‘there was a time when He did not exist.’
What was affirmed was a belief in one God, the Father almighty, creator of all things; and in one Lord Jesus Christ, through whom all things were made and who is the Son of God, the only-begotten of the Father, born of the substance of the Father; true God from true God, begotten not created, consubstantial with the Father; and in the Holy Spirit.
The Holy Spirit is merely mentioned together with the Son and the Father, to indicate belief in the Triad of Father and Son and Holy Spirit, but He is given no further attention. All the conciliar stress was on the Son, His status, and His relation to the Father.
Somewhat surprisingly the Council still used the words ousia and hypostasis as synonyms.
Several points stand out:
The Council Fathers did not use the term Logos for Christ but the more evangelical word Son.
They stressed that He was not created but begotten, not made from nothing but born from the substance of the Father, thus indicating that His was not a metaphorical or adoptive sonship but a real, metaphysical sonship that entailed consubstantiality or community of divine nature between the Father and the Son.
They emphasized His divinity by saying He was not only born of the Father and not created but also was eternal and was God from God, true God from true God.
But the word that has continued to stand out most of all is the word consubstantial or homoousios. What does it mean in the Nicene Creed?
Before Nicea it generally meant ‘of generically the same substance.
For later Catholic theologians it means ‘of identically the same substance.’
For a long time it had been widely assumed that the specific teaching of Nicea was that the Son as consubstantial with the Father had identically the same substance as the Father, and that the Council had thus taught not only the divinity of the Son but also His numerical identity of substance with the Father.
But in recent years there has developed a growing tendency to question and reject this assumption. It is clear that the Council did not explicitly affirm that the Son was ‘consubstantial with the Father’ had the one same identical divine substance as the Father, and hence this was not its specific or formal teaching. But when it said the Son was ‘consubstantial with the Father,’ it meant at least that He is ‘utterly like the Father in substance,’ ‘utterly unlike creatures in substance,’ that He is ‘of the Father’s substance’ and ‘of no other substance.””
But if the Council did not explicitly affirm numerical consubstantiality of Son and Father, was the idea of numerical consubstantiality prominent in the minds of the Nicene Fathers? Today there is a tendency to doubt or deny this also, and for a variety of reasons:
It is urged that if the word consubstantial up to Nicea had only meant generic identity or likeness of substance, it would not suddenly be accepted as meaning numerical identity of substance.
and if it had been so understood then the Eusebians would have cried out ‘Sabellanism.’
Further, it is argued that since the great issue at Nicea was the Son’s full divinity and coeternity and not the unity of the Godhead, the word consubstantial would have been understood to signify the Son’s full divinity, His total likeness in substance to the Father and total unlikeness to creatures in substance.
It is pointed out also that later on when the numerical identity of substance was fully acknowledged, some orthodox theologians still used the word consubstantial in the sense of generic unity.
All this seems to make an impressive case for the view that the Nicene Fathers generally understood ‘consubstantiality’ as likeness in substance. But perhaps an even stronger case can be made for the traditional view that they understood consubstantiality as identity of substance:
Could they have failed to realize that if the Son was ‘of the Father’s substance,’ then He must be like the Father in substance? Why, then, would they add consubstantial if it merely meant ‘like the Father in substance’?
Again, it would seem to be unnatural” for monotheists to admit two divine ousiai. And yet the Fathers must have realized that they would be doing just that if they said the Son was only ‘like the Father in ousia.’
Further, why is it logical to say that the Fathers used ‘consubstantial’ in its Origenist sense of ‘like the Father,’ when they must have known that for Origen it meant ‘like but inferior to the Father,’ while they were intent on affirming the Son’s equality with the Father?
Again, why should the Fathers be unready to accept a new meaning instead of the traditional meaning of this term, if they were ready to use this ‘new’ term itself instead of a traditional Biblical term?
Again, if Hosius of Cordova influenced the adoption of the term, would he have failed to indicate to the Nicene Fathers that for him and the West it signified ‘identity of substance’?
Finally. to all this we might add Athanasius’ declaration that it was the intention of the Nicene decree to go beyond mere likeness and touch identity (De decr. nic. syn. 20).
In the New Testament the eternity and divinity of the Son and the Holy Spirit were indicated clearly enough but nowhere formally declared. There was no formal doctrine about Christ’s origin, nature, relation to the Father and to the Holy Spirit. There was no formal doctrine about a Triune God. But the elements for such a doctrine were there.
In their somewhat infelicitous attempts to explain the Son’s divine status and His relation to the Father by a two-stage theory of a preexistent Logos, the Apologists obscured if they did not deny the eternal personality and the eternal generation of the Son.
Clement and Origen rejected the two-stage theory of the Apologists and maintained the eternal generation of the Son. But Origen, in his attempt to combine strict monotheism with a hierarchical order in the Trinity, ended up by making the Son and the Holy Spirit not precisely creatures but ‘diminished gods,’ inferior to the Father who alone was God in the strict sense.
The stage was set for Arius. He saw in Scripture, the Apologists, and especially Origen two interwoven ideas, one that the Son was God, the other that the Son was subordinate and inferior to the Father in divinity. He saw a tension between these two ideas that the Father alone was God in the strict sense and that the Son was a ‘diminished god’ but not a creature, and he was not satisfied with the tension. He felt it must be resolved, and so he put a blunt question: Is the Son God or creature? He answered his question just as bluntly:
The Son is not God.
He is a perfect creature,
not eternal but made by the Father out of nothing.
And thus the subordinationist tendency in the Apologists and in Origen had reached full term.
The question that Arius put and answered so bluntly was a ‘live’ question, of vital importance to the Christian and trinitarian faith of the Church and one that was deeply disturbing. The Church had to face up to the Arian question and go on record for or against the Arian answer. It did this at Nicea.
Though there may be doubt about the understanding of ‘consubstantial’ at Nicea, there can be no doubt about the historical and dogmatic importance of the Council itself. For there the Church definitively rejected the answer that Arius gave to the question he put: Is the Son God or creature?
The Council firmly rejected Arius’ contention that the Son was a creature, not eternal, and made out of nothing.
It firmly declared that He was begotten, not made, was born of the Father’s substance, was true God from true God, was consubstantial with the Father.
It did more. In the New Testament affirmations about the Son were largely functional and soteriological, and stressed what the Son is to us. Arians willingly recited these affirmations but read into them their own meaning. To preclude this Arian abuse of the Scripture affirmations, Nicea transposed these Biblical affirmations into ontological formulas, and gathered the multiplicity of scriptural affirmations, titles, symbols, images, and predicates about the Son into a single affirmation that the Son is not made but born of the Father, true God from true God, and consubstantial with the Father.
A definitive answer was given to the question of Arius not in the empirical categories of experience, the relational category of presence, or even the dynamic categories of power and function but in the ontological category of substance, which is a category of being.
Nicaea did not describe; it defined. It defined what the Son is, in himself and in his relation to the one God the Father. The Son is from the Father in a singular, unshared way, begotten as Son; not made as a creature. The Son is all that the Father is, except for the Name of Father. This is what homoousion means. This is what the Son is. . . .
The Nicene definition … formally established the statute of the ontological mentality within the Church. It was the precedent for the Councils of Ephesus and Chalcedon, which resolved the issue of the internal constitution of Christ, the Son Incarnate, in the ontological categories of nature and person. . . .
By its passage from the historical-existential categories of Scripture to the ontological or explanatory categories exhibited in the homoousion Nicaea sanctioned the principle of the development of doctrine . . . of growth in understanding of the primitive affirmations contained in the New Testament revelation.”