Someone denounces the Buddha

7. The Buddha said, "Once a man came unto me and denounced me on account of my observing the Way and practicing great loving-kindness. But I kept silent and did not answer him. The denunciation ceased. Then I asked him. 'If you bring a present to your neighbour and he accepts it not; does the present come back to you?' He replied, 'It will.' I said, 'You denounce me now, but as I accept it not, you must take the wrong deed back on your own person. It is like echo succeeding sound, it is like shadow following object; you never escape the effect of your own evil deeds. Be therefore mindful, and cease from doing evil." ~ The Sayings of the Buddha in Forty-Two Sections

Source:
www.purifymind.com/Sutras2.htm