A feature of the age of Ûisang was the tendency to shorten Buddhist texts into brief formulae . Such texts frequently invoked Avalokitešvara or Kuan －( shih ) － yin 觀世音 , a most popular bodhisattva , and were called mantra 眞言 , dharani or “ heart "( gist ) sutras 心經 . Ûisang may have been a devotee of Kuan － yin , for Korean tradition claims that he was a fervent believer in Kuan － yin , founding Naksan Monastery 洛 山寺 devoted to this bodhisattva , and writing a vow dedicated to her . But the attribution of the vow text concerning the dedication to Ûisang has been questioned , and Samguk yusa accounts must be treated with great caution . However , the Korean tradition must have had some basis . Chih － yen is said to have dreamt of Kuan － yin during a life － threatening illness , and was saved by the bodhisattva . As a result , Chih － yen built a Kuan － yin Hall in Yün － hua Monastery 雲 華 寺 , Ch ' ang － an . Like Chih － yen and Hsüan － tsang , Ûisang probably held special veneration for Kuan － yin . Moreover , it is probably no coincidence that seals associated with Kuan － yin in the forms of circular diagrams in one connected line appeared soon after the time of Ûisang , and may have been in circulation before his time . Other Kuan － yin dharanis were formed in a square or vortex pattern , but they are dated to the tenth century . Such dharanis , like the text produced by Ûisang according to the biography written by Ch ' oe Ch ' iwôn , were meant to be burnt as offerings . The name and “ person " of Kuan － yin were thought on the other hand to preserve holders from fire in particular . Perhaps , as the stories of the Wônsangnok and the biography of Ûisang by Ch ' oe Ch ' iwôn indicate , the holy writ could be tested by fire . Fa － tsang recorded the story of a non － believer who threw a copy of the Hua － yen ching into a well . Later , people saw a brilliant light just like violent fire flash out of the well , and when it was fished out of the water after a long time , it was not even damp , which demonstrated the powers of the scripture . This faith in “ chance " can be seen in Chih － yen ' s method of selecting a scripture to study . As the texts and their teaching were too numerous and complex , in the library he let his hand simply fall on a sutra , which happened to be the Hua － yen ching .