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.

[John Calvin] writes clearly, directly, without artifice, and gets straight to the practical heart of the matter.

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.

I'm sometimes asked about my productivity, which I find a bit embarrassing to be honest. I don't really have a particularly interesting answer to this question.

One of the things we in the Reformed tradition are very good at is writing doctrinal theology!

The best Reformed theology isn't just about careful arguments for theologically sophisticated conclusions. It is about how to live the Christian life.

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