俱舍論疏 12.216

12.216

論「由彼有情至六十四劫」，已下答。由上地因勝，所感身壽，其量次長，所感外器亦漸久住。此即善順《施設足》文。第三禪遍淨天，壽六十四劫，七火、一水，總七七火、七水。後七火、一風，七九六十三并一風災有六十四。第六十四雖缺二十二中劫，據全說故，言六十四。此天劫初成時，最初生容壽六十四劫，於後生者皆不得也，若有定業應移餘界。

The treatise says: "Because those sentient beings... sixty-four kalpas," below is the answer. Because the causes in higher stages are superior, the lifespans of the bodies brought about by them are sequentially longer, and the external receptacles brought about also abide progressively longer. This accords well with the text of the Prajñaptipada. In the third dhyāna, the Śubhaktsna devas have a lifespan of sixty-four kalpas: seven fires, one water, totaling seven times seven fires and seven waters. Afterwards, seven fires and one wind: seven times nine is sixty-three, plus one wind disaster, makes sixty-four. Although the sixty-fourth lacks twenty-two intermediate kalpas, based on stating it as a whole, it says sixty-four. When this heaven is first formed at the beginning of the kalpa, those born first may have a lifespan of sixty-four kalpas; those born later cannot attain this. If there is fixed karma, they should move to other world-realms.