I really like Caspar Schwenckfeld. He is one of my favorite reformers. I was turned on to him by reading extracts in Protestant and Radical Reformation readers. He is hardly remembered today by most Protestant Christians, but he was a major figure within the German reformation. Luther disliked him because Schwenckfeld didn't agree with his theology in all points. He was a major supporter of Luther in the beginning, but as Luther became more scholastic and rigid in his views of scripture and more vehement in his my way or the highway attitude, Schwenckfeld went his own way and influenced others in doing so.
Caspar Schwenckfeld Von Ossig was a German nobleman and a lay theologian. He had no degrees of theology, nor was he a trained pastor (which speaks to me personally). His major inspiration came from a revelation he had had and he was obedient to what he thought God wanted him to do based on that revelation. He is often classed among the spiritual reformers (aka spiritualists, but not to be confused with modern necromantic spiritism), such as Hans Denck and Sebastian Franck. I am also quite fond of Denck, but not so much Franck. The spiritual reformers believed in the primacy of the Holy Spirit over biblicalism. They did not disparage the Bible, and often quoted from it, but they believed that one needed to be guided by the Holy Spirit to read the Bible correctly. They attributed all theological division and church strife to the fact that people were not reliant on the Holy Spirit and His direction. In some ways, Schwenckfeld and Denck were precursors to the English Seekers and Quakers, but they were more orthodox in their use of the Bible and in it's interpretation.
Schwenckfeld is remembered by many scholars for his odd doctrine of Christ's heavenly flesh, which was based on his reading of John 6:51. He is an example of Monophysitism in the reformation -which is a subject too involved to be able to get into in this review. His reading of John 6 also influenced his spiritualizing of the communion, whereas Luther believed that the bread actually represented Christ's flesh in consubstantiation as opposed to the Catholic notion of transubstantiation. Schwenckfeld believed that the bread was Christ spiritually, not physically. His view influenced Zwingli and the Anabaptists.
It is rather fascinating to study the debates going on during the reformation period. Often, they will be centered on one group using John primarily and another using the synoptics. Without a doubt Schwenckfeld and Denck were more Johannine than synoptic. It should also be noted that both believed in freewill, whereas Luther and Calvin believed in the total bondage of the will. Luther and Calvin were also heavily dependent on Augustine for most of their theology; Denck and Schwenckfeld may have been familiar with Augustine and may have even liked him, but they also had a strong Eastern (as opposed to Latin) Alexandrian and Cappadocian influence. It should also be mentioned that they were heavily influenced by German Christian mystics like Johannes Tauler. They were way more irenic than Calvin and Luther were as well; those major reformers were often bombastic and rigid in their reformation ideals. Denck and Schwenckfeld (and later Weigel and Boehme) did not believe that anyone could (or should) be forced to accept something that had to be revealed spiritually. They were really ahead of their time in that respect. And that is certainly one of the points I am most impressed by in regards to this branch of reformation thinking.
It is hard to find books by Denck and Schwenckfeld today. I pretty much purchased what was available for both. This book I had to purchase through the Schwenckfelder church library in order to get a copy. I also had to create a profile for it here on goodreads because the book is not widely available. Reformers like Denck and Schwenckfeld need to be better appreciated than they are today. When I first became a Christian, I was strongly Lutheran in disposition, which is odd because I had not read him at that point. Interestingly though, I am descended from Swedish Lutherans; so that may explain it to a degree. As I got older, I became more influenced by the ideas of the radical reformers, which include the Anabaptists and the Spiritualists. I don't agree with everything that they taught, but they really balance some of the things I dislike about Luther and Calvin.
In conclusion, I highly recommend both Schwenckfeld and Denck. This book can be purchased from the Schwenckfelder church library (one has to order by phone, but the number is available on their website) and Denck's selected writings can be purchased from amazon or Barnes & Noble. Both of these reformers have had a profound impact on my growth as a Christian (and as a Protestant) and I cannot recommend them highly enough.