@Merrill Can I suggest The Orthodox Presbyterian Church? They are rather small in number, but probably fit your description and follow Calvinist/Reformed theology the best.
I think the RPCNA, with its
a capella exclusive Psalmody (which characterized early Calvinism due to the strict adherence to the Regulative Principle of Worship) actually is more authentically Reformed Calvinist in terms of worship as it was practiced by the Presbyterians (and also the Puritans and the early Baptists) in the 16th-19th centuries. It was under the influence of Calvinist Methodism, Pietism, and Scoto-Catholicism or Mercersburg Theology (These movements today are kept up by the Reformed Catholic movement) that the current liturgical Presbyterianism with its hymns and beautiful Gothic churches and choirs and the use of liturgical colors, etc, emerged, in both the US and the British Empire.
But before the Calvinist Methodist connexions and the Reformed Catholics of the Mercersburg and Scoto-Catholic movements appeared, and also, I should add, liturgical cross-polination both in the New World as the result of revivals wherein the former Puritans were refined into the admirable Congregationalists with the preaching of the likes of Jonathan Edwards, and in the process, without giving up their Calvinism, began to slowly embrace liturgical trends of the Methodists and Moravians. And in the Old World, furthermore, the Calvinists were increasingly united with Lutheran Church, resulting in a departure from the Regulative Principle of Worship, for example, in Prussia, where the Calvinist nobility had to deal with a Lutheran majority among their subjects as the Kingdom of Prussia rapidly expanded across a variety of historic German and Slavic lands ranging from parts of Lower Saxony to Mecklenburg, West Pomerania, East Pomerania, and right across modern day Poland to Old Prussia. The one common attribute of the Northern German people was Protestantism, primarily Lutheranism, but the Kingdom of Prussia was officially Calvinist, and as such, the Prussian church had to adapt its worship to accommodate Lutheran principles (meanwhile, due to the influence of Pietism, which unfortunately spelt the end for Lutheran Orthodoxy in much of Europe, the Lutherans of Prussia became largely detached from dogmatic considerations, particularly in the East and in areas where they interacted with Moravians and various Slavic reformed churches as well as the Unitarians of Romania and Transylvania.
However, what we now think of as traditional Protestant worship in the most generic liturgy is dominated by the influence of the simpler forms of Lutheran liturgy, specifically the vernacular Lutheran mass, in which the simple four part harmony known as the Chorale, to which the Calvinists merely set psalms, was combined with doctrinally instructive lyrics by Martin Luther, forming the basis of traditional Protestant hymnody, which like the ancient antiphonal hymns of Orthodoxy, which were later introduced into the Western church by St. Ambrose of Milan at a vigil in 386 AD (prior to that time, the Roman church and other Latin churches chanted mainly from the Psalter and mainly in actual monotone, which survives even today in the Roman Catholic, Anglican and Church Slavonic Orthodox liturgies, but which was used exclusively in the Low Mass until the 9th century, when instead it became said quietly or even whispered (and accompanied by an organ in France, which is why France has so much particularly good organ music - most Catholics historically favored, and only ever received communion, at low masses, for at the Solemn Mass only the Priest would partake of the Eucharist, and low masses constituted the majority of masses due to the lack of concelebration, and in France the custom was, when possible, to accompany a low mass with the organ, a distinctly French custom. But at any rate, the idea of a theological hymn which is doctrinally expositional originated in the antiphonal hymnody of the Greek and Syriac churches (St. Ephrem the Syrian was one of the first prolific hymn writers), and St. Ambrose of Milan popularized it in Western Europe, being the first prolific Latin hymn-writer, who also co-wrote Te Deum Laudamus, one of the most beloved canticles in East and West with St. Augustine of Hippo, and much loved for its creedal qualities both by myself and my friend
@MarkRohfrietsch .
But unfortunately, while these hymns remained accessible in the East due to the continued vernacular translation of the liturgy, and indeed, were sung congregationally among both the Russians, with
Znamenny Chant, and the
Prostopinije hymns of the Ruthenian and Lemko people of Central Europe (also historically known as “Red Russians” or Carpatho-Rusyns, in the West, a decrease in Latin literacy and fluency led to these being inaccessible except for choirs, and thus it was Martin Luther who reintroduced to the Western church vernacular and congregational singing of liturgical and didactic hymns that served the purpose of theological (and indeed, musical) instruction. However, initially this was not a part of Calvinist or Anglican worship, and only slowly entered therein, but its adoption by Anglicans and Presbyterians was greatly accelerated by the Methodist movement of John Wesley and its connections to the Moravians, who not only used Lutheran Chorales but wrote many of their own (with some influence, I have heard, from the aforementioned Carpatho Rusyn
prostopinje and other Slavonic hymnography, which makes sense, since the Moravians originated among the Czech people who had historically worshipped in Slavonic before the Austrian conquest of Prague in the 12th century). Likewise, among Continental Reformed Christians, the “shotgun marriage” of Lutheranism and Calvinism not only in Prussia, but also in the Netherlands, where there was a Lutheran minority, and in certain Lutheran countries with a Calvinist minority, resulted in the introduction of Lutheran style hymnody.
This process eventually led to most Protestant churches discarding A Capella Exclusive Psalmody, and only a few, such as the more conservative parts of the Stone Campbell movement, retained a capella music (which I like - I am a fan of A Capella music, but unlike some Orthodox Christians, I also love organ music), and a few others, such as the RPCNA, retained A Capella Exclusive Psalmody, although I have to confess I don’t understand the rationale for it.
Specifically, the verse cited in support of it, using the Regulative Principle of worship, is St. Paul exhorting the Ephesians and Colossians to sing Psalms, Hymns and Spiritual Songs, but that seems to, at a minimum, if read literally, allow for the singing of the many other hymns and canticles, such as the three Evangelical Canticles in the Gospel According to St. Luke, or the Song of the Three Children, or the Hymn of Habakuk, or the Songs of the Suffering Servant, located throughout Scripture, and it was the practice of the early church to sing these, from the beginning, in addition to intoning the Scirpture Lessons when read, particularly the Gospel (a practice inherited from the Jews, who chant the Old Testament using a system called Cantillation). So I personally do not agree with the Regulative Principle of Worship, and there are many aspects of early Calvinist, Congregationalist and Baptist worship I dislike, but much of it is nonetheless interesting and beautiful, and at least one can rest assured that an RPCNA church is never going to crank up the electric guitars and drum kits and make the experience of worship like attending a second-rate rock concert. I could go on to write at length about why Christian Rock music is itself an aberration, but that is beyond the scope of this post or this thread - the point of providing this detailed historical post is to explain why the RPCNA (and the Scottish Covenanting Presbyterians with whom they are associated) represents the most authentically Calvinist worship experience of any remaining denomination that is at least reasonably widespread and accessible.
*Before the Revolutionary War nearly all American Protestants were members of the Congregationalist, Anglican/Methodist, Presbyterian, and Baptist churches, with a smaller number of Lutherans and Dutch Reformed, along with the much smaller Moravian church (the
Unitas Fratrum, originally from the provinces of Moravia and Bohemia in modern day Czechia), where in the Southern states John Wesley had once lived and ministered in a Moravian colony, and also the Mennonite immigrants to Pennsylvania, and the Quakers, famously led by William Penn, but the latter group I regard as being not really on the same page as the Protestants, although there are Evangelical Quakers who are undeniably Christian.**
After the Revolution, the Anglicans became the Protestant Episcopal Church, the Methodists, who were nominally Anglican, became the Methodist Episcopal Church, and most unfortunately, a very large number of Congregationalist churches in Boston as well as certain other historic Congregationalist churches including the oldest surviving church building in the US, the Old Ship Church in Hingham, MA, along with Harvard, which was originally intended as a seminary for training Puritan clergy, were taken over by schismatic Unitarian heretics, who have since, in a great many cases since the merger with the Universalist Church, which was nominally Christian in a more conventional sense, become apostate, under the influence of the transcendentalist theology promoted by the likes of Ralph Waldo Emerson when he was a Unitarian minister. In this respect, they resemble the liberal Quakers who do not worship Christ and care only about “the Inner Light.”**
In the 19th century, we saw the emergence of additional denominations, such as various Restorationist churches including, most successfully, the Stone/Campbell movement with its focus on the weekly celebration of the Eucharist, and more controversial groups such as the Plymouth Brethren, particularly the Closed Brethren led by John Nelson Darby, who were extreme Calvinists and also under Darby became the birthplace of premillenial dispensationalism, and the still more controversial Adventists, and various other groups many of which, such as the Swedenborgians and Mormons, departed from Christian Orthodoxy (as well as some Adventists - outside of the SDA, and even among Sabbatarians, there are a number who reject the doctrine of the Trinity and adhere to Arianism, but within the SDA, thanks largely to Ellen G. White, the Trinity is part of their belief systems, which is why we have a number of SDA friends on ChristianForums). This was followed by the growth in the Holiness Churches, offshoots of Methodism, who kept the doctrine of Entire Sanctification found within John Wesley’s teachings but rejected his liturgical Anglicanism, and the New Thought movement and Spiritism, which mostly led to heretical sects like Christian Science, and from the Holiness Movement we also saw the emergence of another new movement, or pair of related movements, the Pentecostals and Charismatics, who account for a large chunk of the members on Christian Forums.
More recently, the Word of Faith movement seems to combine aspects of New Thought and Charismatic theology, and it is Nicene, but regrettably it tends to be associated with the Prosperity Gospel, with Joel Osteen a prominent exponent of that theological system, which I very strongly disagree with.
** The nature of Quakers makes me regard them as being akin to the Restorationists of the 19th century, except insofar as there are liberal Quakers who reject Christianity altogether, and I get the unpleasant impression these now account for a majority in the UK, but in pre-revolutionary America I expect most Quakers were at least nominally Christian.