法華義疏 10.152

10.152

「爾時佛告」下，第四、合譬，正顯成佛已久。長安舊羅什經本無「一塵一劫」，梁世有僧造《法華經》，感於神夢令安此說。夫論劫者所謂時也。明過去時長，故將塵數劫。言阿僧祇劫者，顯不可數義也。成佛之始尚不可知，一證湛然，寧有終滅？將欲明過去顯當，故明過去不可數。

From "At that time the Buddha addressed..." downward is the fourth part: matching the parable, properly revealing that attainment of Buddhahood was long ago. In the old Chang'an version of Kumārajīva's sūtra, there was no phrase "one dust mote is one kalpa". In the Liang period, a monk produced a copy of the Lotus Sūtra and was instructed by a divine dream to insert this statement. When speaking of kalpas, it refers to time. To clarify that the past time was long, it takes kalpas as numerous as dust motes. Saying asaṃkhyeya kalpas illuminates the meaning of being unreckonable. The beginning of the attainment of Buddhahood cannot yet be known; once realized, it is calm and immutable—how could there be any ending or extinction? Wishing to clarify the past to reveal the future, it therefore clarifies that the past is unreckonable.