preachingly

/ˈpriːtʃɪŋli/
adverb
  1. In a way that gives moral advice or tells people how to behave, often in an annoying or self-righteous manner.
    • She tends to comment preachingly on other people's parenting choices.
    • He spoke preachingly about the need to volunteer more, which made everyone uncomfortable.
    • The editorial was written preachingly, scolding readers for their wasteful habits.