大毘盧遮那成佛經疏 3.16

3.16

經云「復次祕密主！如因月出故照於淨水而現月影像。如是真言水月喻，彼持明者當如是說」者，《釋論》云「月在虛空中行而影現於水，實法性月輪在如如法性實際虛空中，而凡夫心水有我我所相現。又如小兒見水中月歡喜欲取，大人見之則笑。無智者亦爾，身見故見有吾我，無實智故見種種法，見已歡喜欲取諸相，得道聖人笑之也。復次譬靜水中見月影，擾水則不見。無明心靜水中，見吾我憍慢諸結使影。實智慧杖擾心水則不見，以是故說諸菩薩知法如水中月。」持明行者亦如是，由三密方便自心澄淨故，諸佛密嚴海會悉於中現。或自以如意珠身，於一切眾生心水中現，爾時應諦想觀之。今此密嚴之相，從我淨心生耶？從佛淨身生耶？自他實相尚自畢竟不生，何況相違因緣而有所生？又如一切江河井池大小諸器，月亦不來、水亦不去，而淨月能以一輪普入眾水之中。我今亦復如是，眾生心亦不來、自心亦復不去，而見聞蒙益皆實不虛。故當以慧杖攪之，便知無實。不得如彼嬰童，欲作方便取之，以為玩好之具也。既能自靜其意，復當如如不動為人演說之，故曰持明者當如是說。

The sūtra says: “Furthermore, Lord of Mysteries! Just as, because of the moon rising, it shines upon clear water and the reflection of the moon appears, so is the mantra simile of the moon in the water; that vidyādhara should speak in this way.” The Expository Treatise says: “The moon travels in the sky while its reflection appears in the water; the moon-disc of the real nature of phenomena is in the sky of suchness, the nature of phenomena, and the reality-limit, yet the marks of 'I' and 'mine' appear in the water of the ordinary person's mind. Again, like a small child who, seeing the moon in the water, joyfully wishes to grasp it, while an adult seeing this laughs; the unwise are also like this: because of the view of a self they see an 'I', and lacking real wisdom they see manifold phenomena, and having seen them, they joyfully wish to grasp these marks, at which the sages who have attained the path laugh. Furthermore, it is like seeing the moon's reflection in still water, but not seeing it when the water is stirred. In the still water of the mind of ignorance, the reflections of the defilements of self, mine, and arrogance are seen. When the staff of real wisdom stirs the mind-water, they are not seen; for this reason it is said that bodhisattvas know phenomena to be like the moon in the water.” A vidyādhara practitioner is also like this: because their own mind is limpid and pure through the upāya of the three mysteries, the Ghanavyūha ocean-assembly of the Buddhas all appears within it. Or, through their own wish-fulfilling jewel body, they appear within the mind-water of all sentient beings. At that time one should attentively contemplate: does this mark of Ghanavyūha arise from my pure mind, or does it arise from the Buddha's pure body? Since the dharmatā of self and other is fundamentally unborn, how much less could anything be born from conflicting causes and conditions? Furthermore, just as in all rivers, wells, pools, and vessels large and small, the moon does not come and the water does not go, yet the single disc of the pure moon is able to universally enter all waters; so am I now also like this: the minds of sentient beings do not come, and my own mind does not go, yet the benefits gained through seeing and hearing are all real and not false. Therefore, one should stir it with the staff of wisdom and thereby know it lacks reality. One must not, like that young child, employ upāya wishing to seize it as a plaything. Having quieted one's own intention, one should further expound it to others in accordance with suchness, unmoving; therefore it is said that the vidyādhara should speak in this way.