There is no such thing as a stationary tradition. Traditions are always developing, living things.

Jonathan Edwards developed a Calvinistic strand of the doctrine.

There are constraints on what counts as "Reformed." It's more than a name or a label. It's about belonging to a particular theological stream or tradition, which is shaped in important respects by particular thinkers and their work, particular arguments and ideas, a particular community (especially, particular church communities, denominations, and so on), particular liturgies or ways of worshipping and living out the Christian life, and particular confessions that inform the practices of these communities.

In the twentieth century the Reformed tradition was developed in several ways including additional confessions (Barmen, the Belhar Confession, the 1967 Confession of the PC(USA), and so on). It was also significantly augmented by the work of important thinkers like Karl Barth, T. F. Torrance, Jürgen Moltmann, Emil Brunner, Kathryn Tanner, and so on.

That is the great contribution of Reformed thinking to the Christian church: theology for a life well-lived.

There is no such thing as a stationary tradition. Traditions are always developing, living things.

The expansion I have in mind isn't the same as distortion. Of course, there are those who say their views represent Reformed thought, but what they end up with is a caricature of what Reformed thinking is really about. I hope I am not one of those people, but readers [of the Saving Calvinism] will have to make up their own minds on that score!