When reciting the mantra in the mind without voicing it aloud, the sense-object of sound does not exist. The mantra recited in the mind belongs to the mental sense-object (dharma); it is an Image-Only Object, discerned solely by the solitary mental consciousness, without the ear consciousness being involved in discerning it. Because there is no sense-object of sound, the ear consciousness does not arise. When the solitary mental consciousness discerns it, this is called listening with the mind; the recitation is also recited by the solitary mental consciousness.
However, when reciting the mantra, the manas governs and directs the recitation, supervising the mind consciousness in reciting; the manas takes charge and lets the mind consciousness listen, supervising the mind consciousness in listening. In addition, the eighth consciousness provides everything needed, diligently serving. The three consciousnesses together accomplish the mental recitation and mental listening.
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