Linji's "Shout"

A monk asked Linji, " What is the true meaning of the Buddha-Dharma?" Linji came down from his seat, seized the monk, gave him a slap, and then released him. The monk stood frozen. Linji shouted, "Katsu!"

Reflection

Linji's shout 'Katsu!' is a famous Zen wordless tool. When the monk asks for the true meaning of Buddhism, Linji responds with action (seizing, slapping) and then a shout that empties the mind of all conceptual content. The monk's frozen state shows the shock of being wrenched out of habitual thought. The deepest teaching is sometimes wordless and immediate.