Written to support Constantine's agenda of "One God, one Lord, one faith, one church, one empire, one emperor", the Nicene Creed is the first formulation of imperially-sanctioned Christianity. As such, it is accepted by all imperial powers, from Rome to the United States - described as the most ecumenical. What of the writings of the Church before it became wedded to political and military power? Not as 'ecumenical', I suppose.
Interesting, to me, that before empire 'ecumenical' meant diverse and lively and internally conflicting. In the midst of empire, 'ecumenical' means "most widely enforced". If Christianity had never been handed the sword, I wonder what ecumenical would mean now? What it could mean again, after the inevitable fall of our own empire?
The conversion of Constantine and the Roman Empire are at the top, or near the top, of my list of Worst Things to Happen to Christianity. But it is where the Book of Confessions begins.
1.1 'Maker...of all things visible and invisible.' I have always wondered whether this means "perceptible and imperceptible" or whether it literally means "invisible", as in sound waves and concepts and gamma radiation. I tend to assume that it is referring to perceptible and imperceptible, since that would be necessary for God to be maker of "all things".
1.2 Compared to the little bit said about God, Jesus Christ gets a lot of commentary. I go with the assumption that, in cases like this, more is said because more must be said. If there was not disagreement, that is, then this could have been as short as 1.1. Interestingly, a point is made to have Jesus as being of one substance as the father, earlier defined solely as "maker", and the 'making part is repeated. It is interesting to me that given the trinity, we still give Jesus by far the most attention and have the most relational terms between Jesus and God. In contrast, the Holy Spirit is either talked about as itself or as subordinate to God or Jesus - it is "the Spirit of Christ" or "the Spirit of God" but we never say "God of the Spirit" or "Christ of the Spirit", "Son of the Spirit" and so on.
1.3 Here it is, the Holy Spirit "who proceedeth from the Father and the Son". The subordination here is ameliorated by talking about how the Spirit is to be worshiped just as God and the Son are, but immediately we go to the apostolic Church, which in the creeds is often the purview of the Spirit. Given that the Church is also the bride of Christ, accepting Christ as head and leader (the patriarchal view of a proper "bride"), the subordination is hard to ignore.
In short, it is hardest to talk about the Spirit. The Spirit does not have a personal shape like Jesus, and God is such a broad character at this point (existing in every monotheism as well as many civic religions); the Spirit is the ineffable one of the trio. Fires, smoke, clouds, doves, voices, invisible presences, breath on waters, the Incarnator...a lot harder to nail down, and so a lot of our traditional language just subtly places the Spirit below God and Jesus in majesty and in function with the occasional caveat.
For this reason, I think that reasonable Reformed Theology shies away from a robust theology of the Spirit. For that, we'd have to let the mystics and poets in the door. We'd have to learn to say "I don't know". And surely that's not what theology - or empire - is about.