梵網經菩薩戒本疏 5.42

5.42

四、具緣者，一、是殺具，二、有彼想，三、無別開緣，四、故畜，成犯。

Fourth, possessing the conditions [for an offense]: 1. It is a weapon of killing. 2. One has the perception that it is such. 3. There are no distinct circumstances of exemption. 4. One keeps it intentionally. [When these are present,] an offense is constituted.