The Difference Among Reciting the Huatou, Observing the Huatou, and Investigating the Huatou

Watching the huatou is cultivating the power of meditative concentration (samādhi), keeping the mind abiding just before a sentence, without words or language emerging. When the power of concentration is insufficient, words and language will all come out, and the inner voice is ceaseless—this is reciting the huatou. Therefore, it is only when one lacks the power of concentration that the mind repeats a sentence over and over; when there is power of concentration, the inner voice and the appearance of words must both disappear.

When the power of concentration for watching the huatou is sufficient, one can then investigate the huatou, probing into the meaning of this sentence. Words and language almost never appear, and one will not engage in sentimental thinking and intellectual interpretation; only then can there be true realization through awakening, rather than intellectual understanding. For a person with insufficient power of concentration, if awakening is to occur, it can only be intellectual understanding.