What This Concept Is About
In everyday life, our understanding of "sound" is usually built on the mechanical reactions of physics and physiology: vibration of the throat, propagation through air, reception by the eardrum, and finally decoding by the brain into semantic meaning. Such sound necessarily has a beginning, an end, the speaker's subjective intent (the self), and is limited by time and space.
In the Mahāyāna scriptures, however—especially the *Avataṃsaka Sūtra* (《華嚴經》)—「如來音聲」 (Sanskrit: *tathāgata-svara*; also called the Thus Come One's wonderful voice, the sound of all-knowing wisdom, the Thus Come One's speech) is utterly different. It is by no means ordinary sound waves emitted by the Buddha's physical body, but rather **the pure, subtle, wonderful voice that, after the Thus Come One's ultimate liberation, naturally flows forth from the dharma-realm (法界, *dharmadhātu*) in accordance with the faculties and faith-understanding of all beings, pervading the ten directions, and endowed with immeasurable merit and virtue**.
To truly understand 「如來音聲」 (tathāgata-svara, "the Thus Come One's voice"), one must accurately grasp how the classical scriptures define its core essence, its mechanism of operation, and its characteristics:
1. Core Characteristics and Philosophical Essence: Beyond Duality and Effortless Wisdom
The *Avataṃsaka Sūtra* characterizes its essence as: 「非量、非無量；非主、非無主；非智、非無智（唐譯作：非示、非無示）」 ("neither measurable nor immeasurable; neither a sovereign nor without a sovereign; neither wisdom nor without wisdom [the Tang translation reads: neither showing nor not-showing]"). * Not falling into dual boundaries: It is not finite (非量, "not measurable"), yet by no means infinite in the mundane numerical sense (非無量, "not immeasurable"); it is not emitted by a concrete sovereign speaker (非主, "not a sovereign"), yet neither is it blind, disorderly natural noise (非無主, "not without a sovereign"). * Neither inside nor outside, neither born nor destroyed: The scriptures repeatedly emphasize that the Thus Come One's voice 「不從身出，不從心出」 ("does not issue from the body, does not issue from the mind") and 「不從外來，亦不內出」 ("does not come from outside, nor issue from within"). It is like the echo of a valley—the "response to a call": you cannot locate where it accumulates or where it hides. It responds according to what comes, and though the hearer perceives it, there is in reality no graspable entity. * 無功用智 (anābhoga-jñāna, "effortless wisdom"; 無作意, "non-volition"): This is the most crucial philosophical foundation of the Thus Come One's voice. When the Thus Come One emits sounds, there is absolutely no need for the prior deliberation and intention of "I want to speak" that ordinary beings have. It is the effortless response that naturally manifests in the ultimate dharma-realm, powered by the merit and dharma-power accumulated by the Thus Come One through immeasurable kalpas of cultivating all good deeds in the past.
2. Nine Excellent Practices and Metaphors on the Path of Liberation
To help bodhisattvas understand how the Thus Come One's voice operates, the *Avataṃsaka Sūtra* provides an extremely rigorous set of metaphorical correspondences using nine mundane and supramundane phenomena:
1. The four sounds at the destruction of the world (the heavenly-drum sound) metaphor: When the world is destroyed, four sounds of dhyāna bliss and peace naturally arise, guiding beings to abandon desire and ascend to heaven. Likewise, the Thus Come One's wonderful voice, without sovereign and without volition, naturally manifests four kinds of teaching sounds: the first guides beings to cultivate goodness and be born among humans and gods; the second causes them to know the "suffering of conditioned activity" (行苦, *saṃskāra-duḥkha*) and obtain 「音聲忍」 (ghoṣānulomikī-kṣānti, "sound-tolerance"), studying the śrāvaka vehicle; the third guides those who delight in the superior path to study the pratyekabuddha vehicle (緣覺乘); the fourth guides those of sharp faculties to arouse the bodhi mind and cultivate the 大乘 (摩訶衍乘, Mahāyāna, "the Great Vehicle"). 2. The echo metaphor: Like a valley echo—without accumulation, invisible, responding to sounds yet in reality responding to nothing—the Thus Come One's wonderful voice has no fixed locus; it responds to stimuli, and is unknowable and inexpressible. 3. The heavenly wonderful sound metaphor: Just as heavenly wonderful sounds naturally arise in space to awaken heedless devas, so too does the Thus Come One's wonderful voice—without sovereign, without volition, neither arising nor ceasing—universally expound for heedless beings the "sound of non-attachment" (無著聲), the "sound of non-heedlessness" (不放逸聲), the "sound of impermanence, suffering, emptiness, and no-self" (無常苦空非我聲), and the "sound of tranquil nirvāṇa" (寂滅涅槃聲). 4. The good-mouth jewel maiden (善口寶女) metaphor: The jewel maiden "Good Mouth" of the sovereign heaven king can produce a hundred thousand sounds of amusement from a single sound. Likewise, the Thus Come One's voice can 「一音中出無量聲」 ("emit immeasurable sounds from a single sound"), causing each being to understand according to the difference in their vessels of transformation (受化器, the mind-vessel that receives the teaching). 5. The Mahābrahman's brahma-sound (大梵天王梵音) metaphor: When the Brahma king emits his voice, it fills the brahma assembly without going beyond it, and yet all gods and men each think, "The Brahma king today is speaking only to me." Likewise with the Thus Come One's wonderful voice: all who are to be transformed hear it, and each hearer feels, "Today the Thus Come One speaks only for me"—while in reality there is nothing emitted and nothing heard. 6. The water-nature one-taste (水性一味) metaphor: The nature of water has a single taste, yet manifests differences according to the vessel that contains it. Likewise, the Thus Come One's wonderful voice 「唯是一味，謂解脫味」 ("is solely of one taste, called the taste of liberation" [解脫味, *vimukti-rasa*]), and according to beings' 「受化器異」 ("different vessels of transformation") it manifests immeasurable differences of teaching, while the Thus Come One himself is utterly free of discrimination and deliberation. 7. The Anavatapta dragon king's rain (阿耨達龍王降雨) metaphor: Rain does not issue from the dragon king's body or mind, yet it can nourish all grains. Likewise, the Thus Come One's voice neither issues from within nor comes from without, yet universally rains the "nectar of the true Dharma" (甘露正法), nourishing beings' roots of goodness. 8. The Manasvin dragon king's cloud-gathering (摩那斯龍王凝雲) metaphor: The dragon king first raises clouds for seven days without raining, and only after beings have completed their harvest does he gradually release fine rain. Likewise, the Thus Come One first raises the "cloud of Dharma" (法雲) to ripen beings' faculties, and only after their minds are free of fear and alarm does he send down the "nectar rain of Dharma" (甘露法雨), so that beings are not suddenly frightened by hearing the profound emptiness. 9. The great majestic dragon king's continuous rain (大莊嚴龍王連雨) metaphor: The dragon king, with inconceivable power, rains continuously for many days without forming the thought of doing so. Likewise, the Thus Come One, with immeasurable speech, expounds the Dharma in countless differentiated ways without forming such a thought, because the dharma-realm is originally pure and free of distinctions; he merely teaches according to what is appropriate for the sake of liberating beings.
3. Ten Kinds of Measurelessness and the Vessel of Transformation
The Thus Come One's voice possesses measurelessness equal to space (虛空等無量), measurelessness equal to the dharma-realm (法界等無量), measurelessness equal to the realm of beings (眾生界等無量), measurelessness equal to karma and deeds (行業等無量), measurelessness equal to afflictions (煩惱等無量), measurelessness equal to the various sounds (種種音聲等無量), measurelessness equal to desires and pleasures (欲樂等無量), measurelessness equal to the three times (三世等無量), measurelessness equal to wisdom (智慧等無量), and measurelessness equal to the irreversible Buddha-sphere (佛境界不退等無量).
Yet, why can we not hear this wonderful voice that pervades the ten directions? The scriptures point out that this depends on the 「眾生根器（受化器）」 ("the faculties of beings, the vessel of transformation"). If beings are not vessels or are obstructed by heavy afflictions, then in the impure world they can only hear evil sounds; only those whose mind-vessels are pure and whose faculties are mature can sense and hear this all-pervasive, nectar-like, gentle sound, thereby obtaining the liberative experience of "the body becoming cool, the mind settled and unconfused, contemplating equality, neither arising nor ceasing" (身清涼，心定不亂，觀察平等，無生無滅).
A Walkthrough in Everyday Life
To keep this profound doctrine from remaining a mere classical Chinese term, we can conduct a walkthrough using an extremely familiar contemporary scenario—information-feed algorithms and intelligent audio devices—mapping it strictly according to the classical definitions:
Scenario: Scrolling Short Videos Late at Night / Smart-Speaker Podcasts
You cannot sleep late at night, so you open your phone and scroll short videos, or you say to your smart speaker: "I'm so tired, play some sound."
* Wrong mapping vs. correct mapping (different vessels of transformation and the one taste of water): * Misunderstanding: You think that behind the algorithm there is a real "Zhang San" or "Li Si" sitting at a computer, specially selecting a painful and anxious video to push to you, or that the speaker in the video is unilaterally "instilling" thoughts into you personally. * Classical mapping: In fact, the vast data reserves of the algorithm platform (symbolizing the immeasurable dharma-doors contained in the Thus Come One's voice) are themselves only "one water-nature." What you see on your screen depends entirely on your past clicks, dwell time, and preferences—your 「受化器」 ("vessel of transformation") and 「行業」 ("karma and deeds"). * Two people sitting on the same sofa, opening the same app, receive completely different content: the anxious person scrolls into more anxiety-inducing recommendations; the person who is pure and free of desire scrolls into peaceful, soothing music. This is precisely 「唯是一味，隨受化器異而有差別」 ("solely of one taste, with differences according to the vessels of transformation"). The audio itself has no subjective discrimination; it is your own "mind-vessel" that determines whether you hear the "evil sound" or the "pure sound."
* Wrong mapping vs. correct mapping (the brahma-sound metaphor and the echo metaphor): * Classical mapping: When millions of people listen to an excellent podcast or livestream at the same moment, each wearing earphones, each may experience an extraordinarily intimate emotional illusion: "This host really understands me; tonight he is resolving my life's confusion especially for me." * This precisely maps the 「大梵天王梵音喻」 ("Mahābrahman's brahma-sound metaphor")—the devas each think "he speaks only with me," whereas in reality the Thus Come One's wonderful voice is "without emission, without abiding, without any locus" (無出無住，無有方處), like a valley echo (the 呼響喻, "echo metaphor"), responding to your mind's thoughts, while no substantial sovereign is actually conducting a concrete conversation with you personally.
* Wrong mapping vs. correct mapping (the dragon king gathering clouds and gradually sending down the dharma-rain): * Classical mapping: When you first enter a completely new field (for example, studying psychology or spiritual practice), if someone immediately hits you with the most profound and thoroughgoing theory of no-self and emptiness, you may feel extreme panic or even annihilationist despair. * The guidance of a good spiritual friend (the operation of the Thus Come One's voice) is like the 「摩那斯龍王凝雲喻」 ("Manasvin dragon king's cloud-gathering metaphor"): first "raise the cloud of Dharma" to lay the groundwork, guiding you with gentle human-and-heaven good dharmas and life wisdom; only when your psychological capacity (your faculties) is mature does he send down the "nectar rain of Dharma" and speak the profound Dharma, sparing you from terror.
Why Contemporary People Need It
In contemporary society, we are experiencing an unprecedented 「音聲與信息的過載」 ("overload of sound and information"). Every day we are surrounded and torn by noise, workplace PUA, the panic-mongering of marketing accounts, and the clamor of social media. The core significance of why contemporary people need to understand 「如來音聲」 (tathāgata-svara, "the Thus Come One's voice") lies in:
1. Breaking attachment to "discursive power and the sovereign": Contemporary people easily fall into linguistic dualism (black-or-white, who is right and who is wrong). The Thus Come One's voice tells us that the highest expression of wisdom is 「非主非無主，無生無滅」 ("neither sovereign nor without sovereign, neither arising nor ceasing"). The true voice of liberation does not impose itself on others and does not carry the will to control (無作意, non-volition); it is an extremely pure mirror that manifests according to your own mind's capacity. Understanding this allows us, when facing the world's clamorous criticism or praise, to establish a 「音聲忍」 ("sound-tolerance")—knowing that all worldly sounds are like valley echoes, and not being moved by them.
2. Re-examining one's own "mind-vessel (受化器, the vessel of transformation)": Contemporary people often complain that the environment is bad and that they are surrounded by toxic information and speech. But according to the doctrine of the Thus Come One's voice, the dharma-realm is already filled with the pure and liberative "nectar rain of Dharma"; if you can only hear the "evil sound," it is because your own afflictions are piled up and your mind-vessel is defiled. This concept returns the initiative of liberation to the individual: change your mind-vessel, and the world you inhabit and the sounds you hear will change accordingly.
3. A philosophical mirror for the age of AI and technology: Contemporary AI-generated speech (such as generative audio and large language models) may appear capable of "emitting immeasurable sounds from one sound" and "teaching according to the person." But comparing it with the Dharma clearly reveals the limitation: the algorithms of technology are unconscious, cold logic or probabilistic computation, whereas the Thus Come One's voice is the natural outflow of 無功用智 ("effortless wisdom") and the merit and vows accumulated over immeasurable kalpas of compassion. Science and technology can simulate "the myriad transformations of sound," but they cannot supply the 「解脫味」 ("taste of liberation") that causes one to experience "the body becoming cool, the mind settled and unconfused, contemplating equality, neither arising nor ceasing."
Common Misreadings and Clarifications
* Misreading 1: Understanding 「如來音聲」 as the Buddha's speaking voice being very pleasant and charismatic (vocal-cord phonation). * Clarification: Mundane pleasant sounds (such as a singer's voice) are still physical sound waves composed of the four great elements (四大造色, form produced by the four elements), subject to arising and ceasing, and limited. The Thus Come One's voice, by contrast, is a manifestation of the dharma-realm that transcends all marks and cuts off the path of language (超絕眾相、語言道斷). The scriptures explicitly state that it "does not issue from the body, does not issue from the mind, does not come from outside, nor issue from within" (不從身出，不從心出，不從外來，亦不內出), and it can by no means be reduced to sounds produced by physiological vocal cords.
* Misreading 2: Thinking that 「一音普演，隨類得解」 ("one sound universally expounded, each class understanding accordingly") means the Buddha had mastered all the world's languages (e.g., automatic translation into English, French, etc.). * Clarification: This understanding degrades the Dharma into "simultaneous interpretation software." The essence of 「一音普演」 is that the dharma-realm is uniformly endowed with the single taste of liberation (法界同具一解脫味). The Buddha emits the dharma-sound from the state of ultimate non-discrimination, and beings, because of their own karma, powers of understanding, and differing faculties (受化器異, "different vessels of transformation"), decode it in their own consciousness into languages and doctrines that conform to their own cognitive structures. The key lies in the sentient mind's resonance and decoding, not in the Buddha switching languages in his mind.
* Misreading 3: Since the Thus Come One's voice 「周遍法界、無處不至」 ("pervades the dharma-realm, reaching everywhere"), my not hearing it means the Buddha is unfair or un-compassionate. * Clarification: The scriptures use the analogies of water-nature and vessels, and of sunlight and the blind. The sunlight shines universally upon the earth; the blind do not see it, and this is not the fault of the sunlight. The rain falls universally; a broken, overturned bowl cannot hold water, and this is not the fault of the nectar. The Thus Come One's voice is "without sovereign, without volition, without discrimination" (無主無作，無有分別); not hearing it is because beings' afflictions are deep and heavy and they are not vessels (受化器未熟, "the vessel of transformation is not yet mature"). As long as one purifies one's own karmic obstructions through practice and matures one's faculties, one can at any time and in any place enter into this unbroken wonderful voice of the dharma-realm.