From Longman Dictionary of Contemporary Englishbe/feel honour bound to do somethingbe/feel honour bound to do somethingformalSHOULD/OUGHT TO to feel that it is your moral duty to do something We felt honor bound to attend their wedding. → honour
Examples from the Corpus
be/feel honour bound to do something• Don't you tell him either, because he'd feel honour bound to do something about it. 