摩訶止觀 9.22

9.22

《成論》名此「十善相應心」，閃閃爍爍，不應久住。今言欲定坯弱不牢，稱為閃爍，非定如燈焰也。又稱為「電光」者，彼論云：「七依外更有定發無漏不？答云：『有欲界定能發無漏，無漏發疾倏如電光；若不發無漏，住時則久。』」《遺教》云：「若見電光，暫得見道。」如阿難策心不發，放心取枕，即入電光，電光亦是金剛。金剛不孤，因欲界入無漏，無漏發疾，譬以電光，非欲界定得此名也。

The Tattvasiddhi-śāstra calls this 'the mind corresponding to the ten wholesome actions'; flickering and flashing, it should not be dwelled in for long. Here we say that desire-realm concentration is fragile and unsolid, hence called flickering, not that the concentration is like a lamp flame. It is also called 'lightning flash.' That treatise states: 'Beyond the seven dependencies, is there any other concentration that can give rise to the taintless? Answer: There is desire-realm concentration that can give rise to the taintless; the taintless arises swiftly like a flash of lightning. If it does not give rise to the taintless, its dwelling lasts long.' The Yijiao jing says: 'If one sees a flash of lightning, one briefly attains seeing the Path.' As when Ānanda spurred his mind without arising, yet when he relaxed his mind to take the pillow, he immediately entered the lightning flash; the lightning flash is also the vajra. The vajra is not solitary; based on the desire realm one enters the taintless, and the taintless arises swiftly, likened to a flash of lightning; it is not that desire-realm concentration itself receives this name.