The legend does not appear in Sanzo of the Kyoron-ritsu, and it is believed that it was devised to compete with Kyoso Hanjaku (evaluation of sutras) and their verifications of other sects when the Zen Sect was first established.
この伝説は、経論律の三蔵には説かれておらず、禅宗興隆当時に他宗の教相判釈やその実証に対抗するために案出されたものとされている。