Blasphemy is to speak in insulting terms about a deity, religious doctrines or revered persons like saints, prophets or religious leaders. In some traditions, even to express scepticism about such things amounts to blasphemy. In the rough and tumble of the religious world of ancient India, blasphemy and highly critical assessments of one religion by another were fairly common. The Buddha himself was sometimes the target of derogatory and insulting comments and of unfair criticism. Not only did he respond to insults and disparagement with calm or indifference but he advised his disciples to do the same. When he was informed by his disciples that a man named Suppiya was 'finding fault in all sorts of ways with the Buddha, the Dhamma and the Sangha' he said to them: 'Should anyone speak disparagingly of me, the Dhamma or the Saṅgha you should not get angry, resentful or upset because of that. For if you did you would not be able recognize if what they said was true or not. Therefore, if others speak disparagingly of me, the Dhamma or the Sangha you should explain whatever is incorrect saying: "This is not correct, that is not true, we do not do this, that is not our way" ' (D.I,1-3). Having said this he then added an interesting point: 'Should anyone speak in praise of me, the Dhamma or the Saṅgha you should not get proud, puffed up or exultant because of that. For if you did that would become a hindrance to you. Therefore, if others speak in praise of me, the Dhamma or the Saṅgha you should simply acknowledge what is true as true saying: "This is correct, that is true, we do this, that is our way " '.
The Jain teacher Saccaka was proud of the aggressive questioning he subjected religious teachers to when he engaged them in debate. When he ridiculed their ideas or asked them difficult questions he said they would often ‘hesitate, change the subject and display annoyance, anger or resentment.’ After his discussion with the Buddha, Saccaka commented: ‘It is wonderful, really marvellous, how the good Gotama's complexion becomes clear and his face becomes radiant when he is continually spoken to rudely or verbally attacked. It is as you would expect of one who is fully enlightened.' (M.I,250)
Because the Buddha did not get angry when others abused or insulted him, Buddhists do not feel that they have to get angry on his behalf. The Bodhicaryāvatāra makes this point in relation to the desecration of Buddhist shrines and symbols. ‘Hatred towards those who speak insultingly about or damage sacred images or stūpas is inappropriate. The Buddhas do not get angry at such things.’ None of the legal codes of traditional Buddhist cultures included blasphemy as a criminal offence.