瑜伽論記 5.13

5.13

第四無倒無漏進時知有漏退，此中第四與前第二有差別者，前修無漏方便猶未證得謂退曾得定，今第四正得無漏有漏不行謂之為退，故成差別。景云：第二無倒翻初無倒。

The fourth non-inversion: knowing the retrogradation of the tainted when the taintless advances. Regarding the difference between the fourth and the prior second here: formerly, when cultivating the preparatory stages of the taintless, having not yet realized it, one regarded the absorption previously attained as retrograding; now, in the fourth, when directly attaining the taintless, the tainted does not function and this is called retrogradation; hence they differ. Jing says: the second non-inversion inverts the first non-inversion.