梵網經菩薩戒本疏 3.52

3.52

第三、次第者，前戒依過而說所患猶輕，今乃越過加毀為失尤重，是故次後說也。亦是菩薩四波羅夷之中，此居初故先辨也。

Third, regarding the sequence: in the previous precept, speaking in reliance on actual faults was still a relatively light failing; here, going beyond their faults to add deprecation is an especially severe failure, which is why it is explained next. Furthermore, among the bodhisattva's four pārājikas, this occupies the first place, and therefore it is distinguished first.