淨名經集解關中疏 1.40

1.40

於眾言音微妙第一　二法合也。謂出世善言故稱第一。肇曰。殊類異音既善其言而復超勝。

“Among all spoken voices, their speech was subtle, wonderful, and foremost”: Second, the application of the Dharma. This refers to world-transcending wholesome words, and hence is called foremost. Zhao says: “They are adept at the diverse sounds of different kinds of beings, yet their speech is also supremely transcendent.”