Sentence:  It had been as the murmurous consecration to follow the murmurous welcome; and even if it were but part of Aunt Maud's own spiritual <WSD>ebriety</WSD>—for the dear woman, one could see, was spiritually "keeping" the day—it served to Milly, then and afterwards, as a high-water mark of the imagination. 
Meaning of the word marked with <WSD> tags:  The state of intoxication, drunkenness.