This mutuality is expressed in the two characters of kaji: ka (the Buddha's compassion entering the practitioner) and ji (the practitioner's mind absorbing and retaining that compassion).
The second character of kaji, literally meaning 'retaining' or 'holding'; refers to the practitioner's mind absorbing and retaining the Buddha's compassion, likened to water retaining and reflecting sunlight.
ka(Kūkai's analysis of kaji)
The first character of kaji, literally meaning 'adding' or 'increasing'; refers to the Buddha's compassion that pours down upon and enters the practitioner's mind, likened to sunrays falling on water.
kaji(Sokushinjōbutsugi, ch. 5; Shingon Buddhist doctrine)
A Kūkai concept (Sanskrit: adhisthāna) translated variously as 'empowerment' or 'grace,' referring to the mutual correspondence between the Buddha's great compassion and the practitioner's piety, devotion, or faith, through which enlightenment is progressively attained.
mutuality(as used in this Buddhist concept)
A two-way relationship where both sides give something to each other and both are equally involved in the exchange.
The realization of enlightenment cannot be attained on one’s own. For one is not a substantial, i.e., ontologically independent, being to begin with. As the cosmos itself is a web of interdependently originating thing-events, nothing can stand alone to claim complete self-sufficiency. The same interdependency that obtains horizontally between the constituents of the cosmos also obtains vertically. That is, the whole is what it is in virtue of its parts just as the parts are what they are in part