Instructions: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
Input: Which issue was the most divisive amongst the doctrinal pillars established?, Context: In October 1529, Philip I, Landgrave of Hesse, convoked an assembly of German and Swiss theologians at the Marburg Colloquy, to establish doctrinal unity in the emerging Protestant states. Agreement was achieved on fourteen points out of fifteen, the exception being the nature of the Eucharist the sacrament of the Lord's Supperan issue crucial to Luther.
Output:
the Eucharist