I am not sure I understand. homoousian/cibnsubstantial means of one one substance. The Council of Nicea had to be very precise. Arius claimed that Jesus was created by God and subordinate to the Father. The Nicaea Creed was developed so that it was clear and that the heretics of the time could not give ascent to a doctrine with a different meaning than intended. This was affirmed by the Council of Chalcedon affirmed Nicea. I guess what you need to explain is your use of numerical and generically.
Arius did claim that Christ was “created ex nihilo” and his position was (at least in this respect) rejected from the moment he said this very early in the council.
But let me stick to Chalcedon.
Today Catholic say, “I believe in one Lord Jesus Christ, … consubstantial with the Father” (this is the Nicene-Constantinople Creed, but it uses the numeric sense).
They mean that God the Father and God the Son are numerically of on substance. This oneness of substance is not something that exists between a human father and a human son.
At the Council of Chalcedon, the Fathers said that Father and Son (in His divinity) were consubstantial AND Son (in His humanity) and mankind were consubstantial.
The text at Chalcedon is:
Lord Jesus Christ: … consubstantial with the Father as regards his divinity, and the same consubstantial with us as regards his humanity;
What the Fathers at Chalcedon were saying was “the Lord Jesus Christ is consubstantial with the Father as regards His divinity, and the same (Christ) [is] consubstantial with us as regards His humanity.”
I am saying the modern understanding of this is, “the Lord Jesus Christ is consubstantial [in the numeric sense] with the Father as regards His divinity, and the same (Christ) [is] consubstantial [in the generic sense] with us as regards His humanity.”
Further, I am saying that the Fathers at Chalcedon gave no indication that they meant to be using the word consubstantial (really homoousian) in two way across that bit of parallel creedal statement. Thus, the modern way of understanding has was not what the Fathers were thinking about at Chalcedon.
Do you agree that the word consubstantial/homoousian in the Chalcedon creedal statement MUST have two meanings (1. Numeric sense, 2. Generic sense) TODAY? Do you agree that the Fathers as Chalcedon were not trying to communicate two different senses?
That is my position.
I might add that it is very human to understand that a Father and Son are consubstantial in the generic sense. It is my position that how two divine persons are consubstantial in the numeric sense, but not the MODALIST sense is most charitably described as a mystery.
Charity, TOm