Sentence:  But Theodore Parker , commencing his mission to the world-at-large , disguised as the minister of a `` twenty-eighth Congregational Church '' which bore no resemblance to the Congregational polities descended from the founders ( among which were still the Unitarian churches ) , made explicit from the beginning that the conflict between him and the Hunkerish society <WSD>was</WSD> not something which could be evaporated into a genteel difference about clerical decorum . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)