The most scientific explanation of dream interpretation in Pagoda Psychology should be: dreaming of the dead indicates that the dreamer intentionally forgets some unpleasant things in the past and is ready to stand up from setbacks and find himself again, which may represent things that have died in the past and have a meaning of bidding farewell to the past, saying goodbye to the old and welcoming the new; Dreaming of the dead is a symbol of self-detachment and rebirth. Don't be afraid, if the dream is happy, it is an auspicious dream; If the sadness is serious, it means that there is a lot of pressure and emotional instability in the near future, so we should adapt and adjust the pressure accordingly.
From your dream, I dreamed that the dead were lying in the coffin, and the coffin was the place where the body was carried. Dreaming of a dead man lying in a coffin means that you want to forget some unpleasant things in the past, bury them in your heart and start a new ideal life.