菩薩戒本疏 1.40

1.40

結犯輕重有三：一、方便根本相對分別，方便闕緣不遂故輕，根本緣具暢業故重。二、就本中隨境輕重，隨三品境業輕重故。三、就一境中隨心輕重，隨能起心有輕重故。成業亦爾，染不染犯故誤心異，其義可知。

There are three aspects to determining the gravity of an offense: First, distinguishing between application and fundamental offense: application lacks conditions and is not fulfilled, hence it is light; the fundamental offense has complete conditions and completes the karma, hence it is grave. Second, regarding the gravity according to the object within the fundamental offense: it is because the karma is grave or light according to the three grades of objects. Third, regarding the gravity according to the mind with respect to a single object: it is because there is gravity or lightness according to the mind that can give rise [to the act]. The fulfillment of karma is also like this; the intentional and mistaken minds differ regarding defiled and undefiled offenses, and its meaning can be understood.