You can also meditate on emptiness while you walk. This prevents your walking from becoming the cause of samsaric suffering in general and the unimaginable suffering of the three lower realms in particular. Instead, every step becomes a cure for the entire round of samsaric suffering and an antidote to the poisonous root of all delusions, ignorance—not perceiving that the I is empty from its own side. Meditating like this transforms your walking into the cause of liberation, freedom from samsara.
As you walk, ask yourself, ‘‘Why do I say, ‘I’m walking’?’’ Analyze this. The only reason you can find for saying ‘‘I am walking’’ is the fact that your aggregate of body is performing the action called walking, that’s all. Because your skandha of form is performing the action of walking, your mind comes up with the label ‘‘I am walking.’’ Inside your body there appears to you an I that seems to exist from its own side. That’s what you say is walking, but it’s a complete hallucination; it doesn’t exist at all. The I that you say is walking is merely imputed by your own mind. What appears to you and what you believe—a real, truly existent I that is not merely labeled by the mind—is a complete hallucination. It doesn’t exist; it is empty.
You can apply this analysis to all other phenomena—roads, houses, trees, whatever. Just like the action of walking, they too are all merely labeled by your mind. What appears to be real, truly out there, is a hallucination. That is the object to be refuted.
Therefore, as you walk, be aware that in the sense that they all appear from their own side, I, action and object are all hallucinations. Then, no matter how long you walk, as long as you walk mindfully, it all becomes lam-rim, it all becomes a remedy to ignorance, a sword to cut the root of samsara, the root of all suffering.