Idle thoughts are a stumbling block to getting enlightened. Investigating "Who is reciting the Buddha's name?" is a Vajra-king jeweled sword which can cut through all idle thoughts. When Shakyamuni Buddha first accomplished Right Enlightenment beneath the Bodhi Tree, he said, "How strange, how strange! All living beings, without exception, possess the wisdom and virtuous characteristics of the Tathagata (the Buddha). It is because of their idle thoughts and attachments that they cannot certify to them." The Buddha clearly told us why we can't become Buddhas. It's simply because of our idle thoughts and attachments. So we must break through these idle thoughts and attachments. How do we break through them? We use the word "Who?" We drill down into it, drilling until the truth is brought to light. That's when we succeed.
When we meditate, we are investigating the question, "Who is reciting the Buddha's name?" At all times, in the ocean of our consciousness, we look into this question without cease. After doing this for a long time, there will naturally be good news. It's said,
After we sit for a long time, Chan will appear.
After dwelling somewhere for a long time,
we will have affinities.
After sitting for a long enough time, we will experience the states of Chan. And when we live somewhere long enough, we develop affinities with our neighbors. We will share a harmonious relation-ship and live peacefully together.
When we have investigated Chan to the point that our skill is close to perfection, not only will we be free of idle thoughts, but our temper will also be smaller, our afflictions will be fewer, our personality will be noble, and our mind capacity will also be great. At that time, wisdom will come forth. We will understand how to tell right from wrong. We will be able to clearly discriminate between good and evil. We will have washed clean our greed, hatred, and stupidity, so that only the light of precepts, concentration, and wisdom remains, revealing that the Five Aggregates are all empty.