SPEAK NOT HARSHLY
M'avoca pharusam kanci vutta pativadeyyu tam
Dukkha hi sarambha katha patidanda phuseyyu tam.
Don't speak harshly to anyone; those who are thus spoken to will retort.
Malicious talk is indeed the cause of trouble (dukkha) and retribution will come to you. 
Sace neresi attanam kamso upahato yatha
Esa patto'si nibbanam sarambho te na vijjati.
If you can keep yourself calm and quiet, like a broken gong which is no longer resonant,
you are sure to realise Nibbana;1there will be no harshness in you. 
Since the day Kundadhana was admitted to the Order, the vision of a female was always following him. This vision was seen by others, but Kundadhana himself did not see it and so did not know about it.
When he was out on an almsround, people would offer two spoonfuls to him saying, 'This is for you Venerable Sir, and this is for your female companion.' Seeing the bhikkhu going about with a woman, people reported the matter to King Pasenadi of Kosala. They requested the king to investigate this happening. So the king went to the monastery where the bhikkhu was staying.
Hearing noises and voices, the bhikkhu came out and stood at the door, and the vision also appeared not far from the bhikkhu. Knowing that the king had come, the bhikkhu went into the room to wait for him. As the king entered the room, the vision disappeared. When questioned, the innocent bhikkhu replied that he saw no woman. The king wanted to make sure and asked the bhikkhu to leave the room for a while, but when the king looked out, again he saw the woman. But when the bhikkhu returned to the room the woman was nowhere to be found. The king concluded that the woman was not real and so the bhikkhu must be innocent. He therefore paid respects to him and invited the bhikkhu for almsfood.
When other bhikkhus heard about this, they were puzzled and said to him, 'O bhikkhu with no morals! Now that the king, instead of accusing you has invited you for almsfood, you are doomed!' Kundadhana retorted, 'Only you are the ones without morals; only you are doomed because you are the ones who go about with women!`
When the matter was reported to the Buddha, he admonished Kundadhana, 'My son, did you see any woman with the other bhikkhus that you have talked to them thus? You have not seen any woman with them in the way that they have seen one with you. I see that you don't realise that you have been affected on account of a bad deed done by you in the past existence. Now I will explain why you have an image of a woman following you about.'
'You were a deva in your past existence. During that time, there were two bhikkhus who were very much attached to each other. But you tried to create trouble between the two, by assuming the appearance of a woman and following one of the two bhikkhus. For that evil deed you are now being followed by the image of a woman. So, my son, in the future do not argue with other bhikkhus any more; keep silent and strive to realise Nibbana.
- One who follows this exemplary practice, even though not yet having attained Nibbana, is regarded as having attained Nibbana.