瑜伽論記 5.340

5.340

若不如是分別：異類、或時可得者，若不如是分別未來異過現類，或時有疑未來有行生諸雜染可得。

Regarding "if it were not conceptually constructed in this way: being of a different class, it could sometimes be found": if one did not conceptually construct in this way that the future is of a different class from the past and present, there might sometimes be the doubt that future formations could be found to give rise to defilements.