Legends ascribe Kanishka’s fervour for the Buddhist faith not to education but to conversion. His coinage, of which abundant specimens have been preserved, confirms this for it presents images of Greek, Persian, Indian and perhaps Babylonian deities showing how varied was the mythology which may have mingled with Gandharan Buddhism. The coins bearing figures of the Buddha are not numerous and, as he undoubtedly left behind him the reputation of a pious Buddhist, it is probable that they were struck late in his reign and represent his last religious phase.[190] Hsuean Chuang[191] repeats some legends which relate that he was originally anti-Buddhist, and that after his conversion he summoned a council and built a stupa.
The substance of these legends is probable. Kanishka as a barbarian but docile conqueror was likely to adopt Buddhism if he wished to keep abreast of the thought and civilisation of his subjects, for at that time it undoubtedly inspired the intellect and art of north-western India. Both as a statesman and as an enquirer after truth he would wish to promote harmony and stop sectarian squabbles. His action resembles that of Constantine who after his conversion to Christianity proceeded to summon the Council of Nicaea in order to stop the dissensions of the Church and settle what were the tenets of the religion which he had embraced, a point about which both he and Kanishka seem to have felt some uncertainty. Our knowledge of Kanishka’s Council depends chiefly on the traditions reported by Hsuean Chuang[192] which present many difficulties. He tells us that the king, acting in consultation with Parsva, issued summonses to all the learned doctors of his realm. They came in such crowds that a severe test was imposed and only 499 Arhats were selected. There was some discussion as to the place of meeting but finally Kashmir[193] was selected and the king built a monastery for the Brethren. When the Council met, there arose a question as to whether Vasumitra (who is not further described) should be admitted seeing that he was not an Arhat but aspired to the career of a Bodhisattva. But owing to the interposition of spirits he was not only admitted but made president.