The term “sound-hearer [Sanskrit: sravaka]” refers to those who attain enlightenment in quiet cultivation; sound-hearers are essentially an arhat. There is a type of person suitable to cultivate the sound-hearer vehicle – someone with a fiery temperament, rather reclusive, who is fond of quietness can cultivate to be a sound-hearer. Because such people are less inclined towards delivering sentient beings, if they hear about delivering sentient beings they get bothered. Most sound-hearers are those who, seeing that there are people of this world who are difficult to deliver, get impatient and develop anger in their hearts, so they cultivate alone on a mountain. Because sound-hearers are inherently stubborn, short-tempered, and dislike sentient beings, preferring solitary practice, they become sound-hearers. 

We have eighteen arhats here, all of these arhats are sound-hearers. Their sculpted forms are rather fierce looking, and their faces are rather unique. 

Each sound-hearer has something they are particularly stubborn about. 

• Some are not willing to open their eyes their entire lives, saying that seeing everything in the world would pollute their eyes. 

• Some don’t speak a single sentence, because they believe that all verbal karma comes from the mouth, so they shut their mouth like a sealed bottle. 

• Some don’t listen to anything, because they believe that every time others say something it is gossip, with little meaningful talk and much idle chatter. They are not willing to hear much, so they plug their ears. If they hear any sound and it gets into their ears, they quickly run to the river to wash their ears.

These arhats each have their attachments. 

Some totally live on trees, refusing to come down. In the past, there was a Bird Nest Zen Master who also lived on trees and refused to come down, someone told him, “Your living on a tree is dangerous.” 

He said, “I’m never afraid of danger when I am on the tree.” 

We face many dangers living on the flat ground. Walking on the road, sudden car accidents, fires, other than natural disasters there are also “human calamities” between humans. He is actually quite safe living on a tree, because he doesn’t infringe on anyone, others naturally also will not harm him. So sound-hearers actually have their own justifications.