釋氏稽古略 2.33

2.33

沙門帛法橋。誦經乏聲懺悔七晝夜。禱觀世音菩薩以求顯報。至七日喉內豁然。自是晝夜諷詠聲徹里許。年踰九十。聲通婉響（本傳）。

The śramaṇa Bo Faqiao lost his voice while chanting scriptures. He repented for seven days and nights, praying to Avalokiteśvara Bodhisattva for a clear response. When the seventh day arrived, his throat suddenly cleared open. From then on, as he chanted day and night, his voice could be heard from about a li away. Past the age of ninety, his voice remained melodious and resonant (His Biography).