Picture a scene from a western, or from the highlands of Tibet: bandits waiting in ambush at a narrow pass, where the victim has no chance of escape. To really damage someone, one waits till one's intended victim is most vulnerable. What we are told to avoid here is biding our time to be especially hurtful, lashing back at someone maybe weeks or months after they have injured us, whether physically or verbally.
On first hearing verses such as this we may assume they do not apply to us. Obviously, this is meant for malicious people, and we are not among the bad guys. Perhaps this initial response is honest; some of us may hold no grudges. If so, we need not be concerned with this right now; we have certainly practiced well in the past, either in this or previous lifetimes. Let us focus instead on problems that are relevant.
But our initial response may not be very insightful. In meditating on this pledge as well as the others, the point is to examine our past experience and try to recall: Have I done this kind of thing before? What was the context? What prodded me to do it? What were the results? Do I still have this tendency? And in the present, any resentment still active should be brought to light. Am I anticipating revenge? There are ways of getting back at others more subtle than standing at the ready with a shotgun. We need to check for ourselves whether each pledge is pertinent for our present situation, but they are all worthy of clear-minded, honest introspection that does not rely on the initial response, "Who, me?" Maybe, after more reflection, we may say, "Well, yes, at times." This does not mean that we are evil and vulgar, but simply that we have some work to do.
Excerpted from: The Seven-Point Mind Training(first published as A Passage from Solitude : Training the Mind in a Life Embracing the World), by B. Alan Wallace. Copyright 1992 by Snow Lion Publications, Ithaca, New York 14851.
This site provides an on-line database of commentaries on the Tibetan Buddhist meditation practices of lojong (Mind Training) and tonglen.