Thus the Reformed spokesman at the Reformed-Anabaptist disputation in Zofingen (near Bern) agreed that they were “one in the chief points of the articles of faith” and differed on “externals.” But the Anabaptists insisted on enforcing the sole authority of Scripture even more consistently and on implementing the Reformed parallelism of the two sacraments by applying to baptism the same definition of “sign” that Zwingli had applied to the Lord’s Supper (and in his early thought also to baptism). In spite of being “one,” therefore, the two parties could not be united. Roman Catholic polemics, despite the preponderance of Protestant over Roman Catholic theologians in the ranks of the conflict against the Anabaptists, went on tracing the origins of Anabaptism to Luther, but Luther and Calvin both charged that the pope and the Anabaptists were essentially alike in their subjectivism, while the Anabaptists for their part charged that there was no difference between “the papists and the Lutherans” and that “the Lord’s Supper of the preachers” in the established churches, whether Reformed or Roman Catholic, was “false” and “perverted.”

–Jaroslav Pelikan, The Christian Tradition: A History of the Development of Doctrine. Vol. 4, Reformation of Church and Dogma (1300-1700).