Sentence:  [O]ne / Discuss'd his tutor, rough to common men / But honeying at the whisper of a lord; / And one the Master, as a rogue in grain / Veneer'd with <WSD>sanctimonious</WSD> theory. 
Meaning of the word marked with <WSD> tags:  Making a show of being morally better than others, especially hypocritically pious.