仁王護國般若波羅蜜多經疏 2.246

2.246

解曰：言示導者，開示引導。言應化者，即他受用及大小化，通名應化。應化所依清淨法界，與此能依體非即離故，說應化俱名法身。謂諸如來普遍法界應現三界，亦同所化，云不離故。從此第三簡外道非。

The commentary states: 'Display and guide' means revealing and leading. 'Response and transformation' refers to the body of enjoyment for others and the great and small transformation bodies, which are collectively called response and transformation. The pure dharmadhātu upon which response and transformation depend is neither identical to nor separate from the substance of these which depend upon it; therefore, response and transformation are both called the Dharmakāya. That is, the Tathāgatas pervade the dharmadhātu and manifest in response within the three realms, also harmonizing with the transformed; hence it is said they 'do not depart'. From here, the third part distinguishes the errors of non-Buddhists.