A BRAHMANA IS HE WHO GIVES OFFENCE TO NONE
Akakkasam vinnapanim giram saccam udiraye
Yaya n' abhisaje kinci tam aham brumi brahmanam.
He who speaks gentle, instructive and true words, and who does not offend anyone by speech, - him I call a brahmana. 
Venerable Pilinda Vaccha had a very offensive way of addressing people. He would often say, 'Come here, you wretch,' or 'Go there, you wretch' and such other things. One day several bhikkhus complained about his conduct to the Buddha. The Buddha sent for Vaccha, and spoke to him on the matter. Then on reflection, he found that for many past existences, Vaccha had been born only in the family of brahmins, who regarded themselves as being superior to other people. So the Buddha explained, 'Bhikkhus! Don't be offended with Vaccha. He addresses as 'wretch' only by force of habit acquired in the course of his many previous existences as a brahmin, and not out of malice. He has no intention of hurting others, for an Arahant does not harm others.'