The bodhisattva's speech is unlimited—thus it can be understood by all, regardless of ability or language. It could thus be understood as communicative content, rather than sound, which is inherently limited. The bodhisattva's speech is inherently free from bad qualities and always true. They could declare the number of leaves on a tree without looking at it—we could thus say that their speech is not so much the intentional arousal of words (like we perform) but the very content of reality as expressed in words. Bodhisattva speech is the manifestation of the unconditioned truth free from contingency or limits.
The Bodhisattva's Speech Accords with all Sentient Beings
A bodhisattva's speech accords with birthplaces (i.e. language).
They are based on characteristics and yet are free from obscurations or attachments.
Thus, they can speak to all sentient beings, including insects and butterflies.
Their explanations of the Dharma are without loss, and neither increase nor decrease, like space.
Their speech can accord with (be understood by) all kinds of beings, such as devas. Their speech thus surpasses that of all devas, including brahmās and kiṃnaras.
Hearing their voice, beings give rise to bliss and intentions to practise the Dharma.
Māras turn to renounce their evil, and the deaf and dumb are made immediately to be able to speak and listen well.
The Speech of the Bodhisattva is free from all Bad Qualities
A bodhisattva's speech is free from greed, anger, ignorance, contradiction, harshness, pride, aversion, and dozens of other negative qualities.
Overall, it is characterised by being free from extreme, unbeneficial, or dualistic qualities.
A Bodhisattva Always Speaks the Truth
The words that come forth from a bodhisattva have the power of supernormal knowledge. They are the fruit of their accomplishments.
If someone asks a bodhisattva to specify the number of leaves on a tree, or grains of sand in the Ganges, a bodhisattva can reply correctly without looking at or counting the number. Only a buddha-tathāgata can know and verify this degree of truth.
A Past Life Example of the Perfect Speech of a Bodhisattva
In the distant past, Vajrapāṇi relates how the sage Surāga was leaning on the side of a nyagrodha tree and counted the number of leaves with his supernormal power while reciting the Ṛgveda.
The wandering brāhmaṇa Śyāmatva came to the tree and exchanged words with Surāga.
Surāga asked whether Śyāmatva knew if there was a person in the world who knew the number of leaves on that nyagrodha tree.
Śyāmatva replied that he knew. Surāga was astonished. Śyāmatva proceeded to give the number of leaves, in verse, in several different kinds of units.
Surāga praised him and asked whether any other sages told him the number.
Śyāmatva said that he knew while in the human realm, and that his words were the "truth" and so they could not be lies.
Vajrapāṇi reveals that Surāga, at that time, was Śāriputra, and Śyāmatva was Śākyamuni Buddha.
He declares that this is the secret of the bodhisattva's speech, and if someone understands only a little of this, they are supreme among the wise.