俱舍論記 12.131

12.131

「由彼有情至六十四劫」者，答。故《正理》云「何緣七火方一水災？極光淨天壽勢力故。謂彼壽量極八大劫，故至第八方一水災。由此應知，要度七水、八七火後乃一風災。由遍淨天壽勢力故，謂彼壽量六十四劫，故第八八方一風災。如諸有情修定漸勝，所感異熟身壽漸長，由是所居亦漸久住。」

"Due to those sentient beings... sixty-four kalpas" is the reply. Therefore, the Nyāyānusāra states: "For what reason are there seven fires before one water disaster? It is due to the power of the lifespan of the Ābhāsvara devas. That is, their lifespan is at most eight great kalpas, so only at the eighth does a water disaster occur. From this it should be known that only after passing through seven waters and eight times seven fires does a single wind disaster occur. It is due to the power of the lifespan of the Śubhakṛtsna devas; that is, their lifespan is sixty-four kalpas, so at the eighth eight does a single wind disaster occur. As sentient beings gradually excel in the cultivation of dhyāna, the karmically resultant bodies and lifespans they receive become gradually longer, and consequently their abodes also remain established gradually longer."