Here is a lengthy quote from Thomas Torrance describing how an Evangelical Calvinist ‘Doctrine of God’ differs from a Classic/Federal/Roman Catholic ‘Doctrine of God’. He is taking a look how John Knox articulated this difference in the ‘Scots Confession’; you’ll notice how important “order” is, relative to the differing emphases of the disparate confessions and catechisms being considered.

In this Reformation theology of John Knox and his colleagues there took place a radical shift from the medieval set of mind, away from an abstract theology of logically ordered propositions to a lively dynamic theology, addressed not primarily to the salvation  of the individual soul, but to the nation as a whole. It involved a radical change in the doctrine of God. This is very evident in the first article of the Confession on the doctrine of the Holy Trinity: ‘ane onlie God . . . ane in substance, and zit distinct in thre personnis, the Father, the Sone, and the holie Gost’. Thus in the Scots Confession as in John Knox’s Genevan Liturgy, the doctrine of the Trinity is not added  on to a prior conception of God — there is no other content but the Father, the Son, and the Holy Spirit. There was no separation here between the doctrine of the One God (De Deo Uno), and the doctrine of the triune God (De Deo Trino), which had become Roman orthodoxy through the definitive formalisation of Thomas Aquinas. This trinitarian approach was in  line with The Little Catechism which Knox brought back from Geneva for the instruction of children in the Kirk. ‘I believe in God the Father, and in Jesus Christ his Son and in the Holy Spirit, and look for salvation by no other means.’ Within this trinitarian frame the centre of focus in the Confession and Catechism alike is upon Jesus Christ himself, for it is only through him and the Gospel he proclaimed that God’s triune reality is made known, but attention is also given to the Holy Spirit. Here once again we have a different starting point from other Reformation Confessions. Whereas they have a believing anthropocentric starting point, such as in the Heidelberg Catechism, this is quite strongly theocentric and trinitarian. Even in Calvin’s Institute, which follows the fourfold pattern in Peter Lombard’s Sentences, the doctrine of the Trinity is given in the thirteenth chapter within the section on the doctrine of God the Creator. Calvin’s Genevan Catechism, however, understandably followed the order of the Apostles’ Creed. The trinitarian teaching in the Scots Confession was by no means limited to the first article for it is found throughout woven into the doctrinal content of subsequent articles. (Thomas Torrance, “Scottish Theology,” 3-4)

Still here? This delineates how “EC” substantially moves away from the Thomist doctrine of God presented by Classic Calvinism (as well as most of “Evangelical” theology — meaning in the vein of Ryrie, Grudem, Erickson, et al.). I won’t say much here, except to highlight the importance of Torrance’s point on ‘Classical’ theologies’ separation or wedge between the “single substance” of God versus the “thrice personages” of the Trinity. In other words, “EC” doesn’t start with a notion of “God,” and then add on the persons of the trinity to that notion; instead “EC” grounds the being of God in the very relation of the Father, Son, and Holy Spirit.

That’s all I’ll say for now, for questions, or objections I’ll see you in the comment meta . . .