In the early 16th Century, the movement objecting to the flagrant greed and corruption in the Roman Catholic Church, now known as the Protestant Reformation, got under way in earnest. In 1517 in Germany, Martin Luther posted his “Ninety-Five Theses.” At about the same time in Switzerland, Huldrych Zwingli launched a reform movement with a remarkably similar set of “Sixty-Seven Conclusions.” The recently-introduced printing press helped spread these ideas rapidly from place to place, but unresolved differences kept the reform movements separate. At the time, the prospects of reform looked remote, as the Church, most governments, the ruling classes and civil society supported the continuance of the status quo.
In 1529, the German Prince Philip of Hesse saw potential in creating an alliance between Luther and Zwingli, realizing the strength of a united Protestant front to fight the entrenched elite. He convened a meeting, now known as the infamous Colloquy of Marburg. At the gathering, Luther and Zwingli agreed on everything except one doctrinal issue: was Jesus Christ spiritually present at a mass? Zwingli asserted no, while Luther insisted yes. In the debate, Luther became so angry that he carved his rejection into a table in the meeting room. (Some critics suggest that egos also played a role: if the strong-minded protagonists had been able to resolve their differences about the spiritual presence of Christ, another issue would have emerged to preclude agreement.)