High orthodoxy, then, is the era of the full and final development of Protestant system prior to the great changes in philosophical and scientific perspective that would, in the eighteenth and nineteenth centuries, utterly recast theological system into new forms.
There is perhaps some justification in dividing seventeenth-century orthodoxy into two phases.
The first is a phase of polemical codification during which theologians like Hoornbeeck, Cloppenburg, and Voetius developed primarily polemical systems in response to all known adversaries past and present, including the variant theologies that had developed within the bounds of the Reformed confessions.
The second is time both of final fruition and decline, following 1685, when the tendency was toward the creation of a theological synthesis in which the results of Protestant exegesis, the dogmatic forms of Protestant doctrine, the polemical establishment of those doctrines, and an exposition of the practical implication of doctrine could be gathered into a systematic whole, as witnessed by Mastricht at the very end of the seventeenth century—and at the same time the exegetical and philosophical norms of the tradition were failing and the possibility for confessional homogeneity had begun to disappear, as witnessed both in England and Switzerland, by 1725.
Nevertheless, the entire period from 1640 to the beginning of the eighteenth century bears witness to a confessional homogeneity and to a fairly consistent development of the language of scholastic Protestantism as set forth by the great formulators of system in and following the era of confessional synthesis.
By 1640 the theologians of the era of Dort were being replaced by pupils and successors, and the final codification, both of polemics and of positive dogmatic theology, had begun in the Reformed Church.
This work of the final codification of orthodoxy was complete by 1685 in the works of Cocceius, Voetius, Maresius, Hoornbeeck, Turretin, and Heidegger and preserved by writers like Mastricht, Witsius, Marckius, Pictet, Van Til, Vitringa, and Boston, until the second decade of the new century.
Muller, R. A. (2003). Post-Reformation Reformed Dogmatics: The Rise And Development Of Reformed Orthodoxy; Volume 1: Prolegomena To Theology (2nd ed., pp. 80–81). Grand Rapids, MI: Baker Academic.
After this, Muller had noted:
By 1725, a fairly uniform and unified confessional subscription had faded both in England and in Switzerland … Theology after 1725, in what can be called “late orthodoxy,” is less secure in its philosophical foundations, indeed, searching for different philosophical models, less certain of its grasp of the biblical standard, and often (though hardly always) less willing to draw out its polemic against other “orthodox” forms of Christianity, less bound by the confessional norms of the Reformation, and given to internecine polemics. .. One can even speak here of a “deconfessionalization” in the late orthodox era that reverses the process of “confessionalization” that took place in the late sixteenth and early seventeenth centuries (pg 32).