大般涅槃經義記 4.318

4.318

就業障中，五逆罪重，故偏說之。就報障中，謗法闡提應是業障，何故名報？以此二種多世積習方始成就，故說為報。「如是三」下總以結之。餘願可解。

In the obstacle of karma, the five heinous sins are heavy, and therefore are singled out. In the obstacle of retribution, slandering the Dharma and icchantikas should properly be the obstacle of karma; why are they called retribution? Because these two kinds are accomplished only after accumulation and habituation over many lifetimes, they are called retribution. From "These three" down, it concludes them in general. The remaining vows can be understood.