This paper reports a careful investigation of the citations of the Zongjing lu 宗鏡録 (Record of the axiom mirror) in the Kōzen gokokuron 興禅護国論 (Introducing Zen to protect the nation), with special attention to the background and intentions of Eisai’s 栄西 (1141–1215) use of the Zongjing lu.
There are four examples of citations of the Zongjing lu in the Kōzen gokokuron which use can be roughly divided into three. (1) In the first two citations, Eisai uses the Zongjing lu to refute the criticisms of the Tendai sect that Zen “has an evil misunderstanding of the doctrine of emptiness” (悪取空) and are “falsely enlightened” (暗証). (2) In the next example, Eisai cites the Zongjing lu to differentiate himself from Nōnin 能忍, who “lacks practice and cultivation” (無行無修), and to refute Tendai, which oppressively viewed them as the same. (3) In the last example, Eisai uses the Zongjing lu as a skillful means for entering Buddhist practice based on the point that it collects important phrases from the Buddhist canon.
From the above it can be seen that Eisai, under the specific conditions of the Tendai sect suppressing Nōnin and Eisai, used the Zongjing lu to prove that the new Zen he brought was an orthodox Buddhism not in contradiction to Tendai or the other then-extant sects of Japanese Buddhism.