Sentence:  ... the "Gift of Prophecy" ... was in the mind not as an "Inhabitant, but as a Guest;" that is, by <WSD>intermittent</WSD> "Returns and Ecstasies," by "Occasional Raptures" and "Revelations;" as is clear from what we read of the Prophets in the Old Testament. 
Meaning of the word marked with <WSD> tags:  Stopping and starting at intervals; coming after a particular time span.