四分戒本疏卷第一．第二．第三 3.21

3.21

堀地戒第十　多於三種益故不聽堀地壞生。一為不惱害眾生故。出家修慈宜愍物命。二為止誹謗故。三為大護佛法故。若佛不制此二戒者。國王大臣役使比丘。由佛制故王臣息心不復役使。得令靜緣修道發智斷或。是名大護　別緣有五。一是生地。二作生地想。三自堀。四使人堀時不作知靜語。五隨傷便犯。已下正明戒本。此因六群為修治溝堂故自堀地。居士譏嫌。比丘舉過。佛為制戒。

The tenth precept: digging the earth.
The prohibition against digging the earth and harming living beings is due to three benefits: First, not to harass and harm living beings: a monastic cultivating compassion should pity the lives of creatures. Second, to stop slander. Third, to greatly protect the Buddha-dharma: if the Buddha had not instituted these two precepts, kings and ministers would have conscripted bhikṣus into labor; because the Buddha instituted it, kings and ministers abandoned that intention and no longer conscripted them, enabling a quiet environment to cultivate the path, arouse wisdom, and sever delusion. This is called great protection.
There are five specific conditions: 1. living earth; 2. perceiving it as living earth; 3. digging oneself; 4. not using permissible speech when instructing another to dig; 5. incurring the offense as soon as damage is done. The text of the precept is properly explained below. This arose because the group of six dug the earth themselves to repair a ditch and hall, which laypeople criticized. The bhikṣus reported the fault, and the Buddha instituted the precept for them.