Nārada Bhante:
Your body is as beautiful as an angel and you are floating in the sky. But your mouth is being eaten by worms and is very smelly. What have you done in your previous life?
Ghost:
I was an evil monk and insulted others using bad words. I pretended to be a good monk. I did not control what I said to others. However, I did not do any evil actions with my body. Because of this, my body is beautiful but my mouth is full of worms.
You have seen this with your own eyes, Nārada Bhante. The wise and compassionate Buddhas have taught about wholesome things. I say the same to you. Never tell lies or break friendships with divisive speech. Then you will be reborn in heaven and enjoy every happiness you desire.
Read this translation of Petavatthu 1.3 Pūtimukha Sutta: Stinky Mouth by Ven. Kiribathgoda Gnananda Thero on SuttaFriends.org. Or explore the Pali on DigitalPaliReader.online.
You can find the entire translation of the Petavatthu: Stories of Ghosts available on SuttaFriends.org.