瑜伽論記 12.210

12.210

第三精進能轉不轉中，意謂地前行有興廢同住菩薩得有超，初地上無起，中劫者刀兵劫也，大劫者水火劫也。

In the third part, on vigor being capable of transforming or not transforming, the meaning is that before the bhūmis, practice fluctuates between progress and decline, and bodhisattvas dwelling at the same stage can surpass [one another]; from the first bhūmi onward, no [decline] arises. A medium kalpa is a kalpa of weapons; a great kalpa is a kalpa of water and fire.