大般涅槃經義記 5.63

5.63

觀苦相中，先觀生苦，文別有三：一明生過、二約之辨觀、三總結之。

In contemplating the marks of suffering, first the suffering of birth is contemplated, with three distinct parts in the text: first, explaining the faults of birth; second, discerning contemplation based on them; third, generally concluding.