Sanctimoniously tells you HOW someone speaks or acts when they put on that 'I am better than you' moral face. He smiled sanctimoniously. She spoke sanctimoniously about other people's mistakes. The feeling is the same as sanctimonious — always a frown, a bit formal, a bit sharp — but this form sits on a verb. People stretch it the same way, to any lecturing tone, not only a church tone. Though actually, in easy talk many speakers skip this long adverb and say in a sanctimonious way, or they just use the adjective. You will still meet the -ly form in writing.

道貌岸然地、自以為高尚地