From Nagarjuna's Treatise on the Great Perfection of Wisdom
(Dharmamitra Translation)

There are those who say that this "not killing" precept may be categorized as "good" or it may be "neutral."

Question: According to the testimony of the Abhidharma, all moral regulations associated with the precepts are good. Why then do you now say that they may be "neutral"?

Response: According to the abhidharma of Kaatyaayaniiputra they are all categorized as "good." According to the statements contained in the other abhidharmas, the precept of not killing may be good or it may be neutral. Why? If it were the case that the not killing precept were always good, then it ought to be the case that those who uphold this precept should never fall into the wretched destinies as is the case with those who have achieved the Way. For this reason there may be times when it should be neutral. Because that which is neutral has no resulting retribution it may be the case that one is not then reborn in the heavens or among men.

Question: It is not the case that one would falls into the hells based solely on the neutrality of a precept. It is because of the additional factor of the production of an evil thought that one falls into the hells.

Response: By not killing beings, one develops an immeasurable quantity of good dharmas. This is because the creating of merit through non-commission [of killing] is accumulating constantly day and night. However, if one is [simultaneously] committing a few karmic offenses, [one's merit] then becomes limited and measurable. How is this so? [One's merit situation] gravitates towards that which is measurable and does not go the way of the immeasurable. For this reason one can know that within the sphere of the not killing precept, there may be instances in which it is "neutral."

Moreover, there are those people who do not receive the precepts from a Master but who only bring forth in their minds a vow to themselves, "From this day on, I shall no longer kill any beings." The not killing of this sort may have times when it is neutral.

Question: To which of the realms is this precept of not killing connected?

Response: According to the statements in the abhidharma of Kaatyaayaniiputra all moral regulations associated with received precepts are connected to the desire realm. According to statements in the other abhidharmas it may be connected to the desire realm or may not be connected [to any realm] at all. To speak of it in a way which corresponds to reality, there are three ways of classifying it: It may be connected to the desire realm; it may be connected to the form realm, or it may be [connected to] states beyond outflows. Although the dharma of killing beings is specific to the desire realm and thus the desire realm's not-killing precept ought to correspond in its connections to killing's presence in the desire realm, still, because in the form realm and formless realm one is far removed from engaging in killing, those cases constitute the true precept of not killing.

Furthermore, there are those people who do not take the killing precept but who from birth onwards do not take pleasure in killing beings. As for [not killing's] being perhaps good or perhaps neutral [as mentioned above], this case qualifies as neutral. This dharma of not killing is not a mind dharma, it is not a dharma belonging to the mind and it is not a dharma interactive with the mind either. It may arise in association with the mind or it may be that it does not arise in association with the mind. It is stated in the abhidharma of Kaatyaayaniiputra that not killing beings is either body karma or mouth karma. It may involve apparent or nonapparent form. It may be that it conforms with the actions of the mind or it may be that does not conform with the actions of the mind. (The notes in red say, "conforming with the mind" refers to precepts coexisting with absorption. Not conforming with the mind refers to the five precepts.") It is not the case that it constitutes karmic retribution from earlier lives. There are two types of cultivation. This does correspond to cultivation. There are two types of realization. This does correspond to realization. (The notes in red state, "This refers to physical realization and wisdom realization.") There is severance through thought. In all desire realms it is the last to be achieved. There is severance through seeing and severance over time. That which is gained by both the common person and the arya is a form dharma. It may be visible or it may be invisible. It may be a dharma which is opposable or it may be a dharma which not opposable. It is a dharma which has a reward. It is a dharma which has a fruition. It is a dharma in the sphere of outflows. It is a conditioned dharma. It is a surpassable dharma. (The notes in read state, "It is 'surpassable' because it is not ultimate.") It is a non-corresponding cause. Analyses such as these refer to the precept proscribing killing.

Question: According to the eightfold direct path's preceptual standard as well, the killing of beings is proscribed. Why do you merely state that the precept of not killing beings has a retribution and is in the realm of outflows?

Response: We discuss herein only the regulatory dharmas associated with taking the precepts. We do not discuss here the regulations associated with being without outflows. Moreover, in other abhidharmas, it is stated that the dharma of not killing does not follow along with the actions of the mind, that it is not the case that it constitutes karma of the body or mouth, that it is not aligned with the karmic activity of the mind, that there may be a retribution or may not be a retribution, that it is not a dharma interactive with the mind, and that it may be in the sphere of outflows or it may be in the sphere of no outflows. These are dharmas which vary [in their analysis from author to author]. The others are all [analyzed] identically.

Moreover, there are those who say that buddhas, worthies and aryas do not engage in frivolous debate about dharmas. (The notes in red state: "'Frivolous' refers to all sorts of unorthodox discussions.") Whichever being one confronts, in each and every case, it cherishes its own life. Therefore the Buddha said, "Do not take another's life. If one takes another's life, in life after life one will undergo all manner of bitter pain." The existence or nonexistence of beings shall be discussed later on.