四分比丘戒本疏 2.89

2.89

第六十四、覆藏麁罪者，夷殘二聚。并出血、破僧蘭罪，名為麁罪。覆至明相出時，犯提也。

The sixty-fourth, concealing a grave offence: This refers to the two classes of pārājika and saṃghāvaśeṣa. Together with shedding [the Buddha's] blood and causing a schism in the Saṃgha, which are thullaccaya offences, these are termed 'grave offences'. Concealing it until the dawn appears incurs a prāyaścittika.