Since the Arminian controversy, the Reformed tradition—as a branch of Protestantism distinguished from Lutheranism—divided into two separate groups, Arminians and Calvinists.However, it is now rare to call Arminians a part of the Reformed tradition, as many see these two schools of thought as opposed, making the terms Calvinist and Reformed synonymous.Baylor University professor of theology Roger Olson, author of , is a bit surprised that the site, which hosts nearly 800 members and has borne 37 reported marriages, is catching on.
Nevertheless, the term first came out of Lutheran circles.
Calvin denounced the designation himself: Despite its negative connotation, this designation became increasingly popular in order to distinguish Calvinists from Lutherans and from newer Protestant branches that emerged later.
Even though the vast majority of churches that trace back their history to Calvin (including Presbyterians, Congregationalists, and a row of other Calvinist churches) do not use it themselves, since the designation "Reformed" is more generally accepted and preferred, especially in the English-speaking world.
Moreover, these churches claim to be—in accordance with John Calvin's own words—"renewed accordingly with the true order of gospel".
The term Calvinism can be misleading, because the religious tradition it denotes is and has always been diverse, with a wide range of influences rather than a single founder. Reformed churches may exercise several forms of ecclesiastical polity, but most are presbyterian or congregationalist with some being episcopalian.