四分比丘戒本疏 2.42

2.42

Tenth: the precept against digging the earth. This refers to damaging earth that is moist and capable of growing grass and trees. According to the Mahāsāṃghika-vinaya, damaging an amount like a mosquito's leg incurs a prāyaścittika. If digging is necessary, one should instruct a kappiya-kāraka, saying: 'Look at this, know this.' If one directly tells him, 'Dig this,' it incurs a prāyaścittika.