Chinese Opera like western opera evolved and was / is based on fact, fiction, folklore etc. See the links below
Baishui Li has written: 'Ping ju hui kan' -- subject(s): Chinese Operas, Operas, Chinese
Catherine Crutchfield Swatek has written: 'Peony Pavilion onstage' -- subject(s): Chinese Operas, Chinese drama, History and criticism, Operas, Chinese
Usually operas are not based on religious themes. You may be thinking of oratorios.
Lin-jui Chen has written: 'The Peking opera' -- subject(s): Chinese Operas, History and criticism, Operas, Chinese
Jinliang Zhang has written: 'Zhongguo xi qu lian pu' -- subject(s): Chinese Operas, Operas, Chinese, Theatrical makeup
Operas are not necessarily choral works or based on religious themes.Cantatas are.
Yongjian Wang has written: 'Kun qiang chuan qi yu nan za ju' -- subject(s): Chinese Folk drama, Chinese Operas, Folk drama, Chinese, History and criticism, Operas, Chinese
Zhizhang Wang has written: 'Zhongguo jing ju bian nian shi' -- subject(s): Chinese Operas, History and criticism, Operas, Chinese
Xiangheng Zheng has written: 'Zhongguo xi qu di chuang zao yu jian shang' -- subject- s -: Chinese Operas, Chinese drama, History and criticism, Music, Operas, Chinese
Wenfeng Ou has written: 'Xianggang dang dai Yue ju ren ming lu' -- subject(s): Biography, Chinese Operas, Operas, Chinese, Singers
Shuren Ni has written: 'Er jia xian chang qiang yin yue chu tan' -- subject(s): Chinese Operas, History and criticism, Operas, Chinese
Ning Wang has written: 'Kun qu yu Ming Qing yue ji' -- subject(s): Chinese Folk drama, Chinese Operas, Folk drama, Chinese, History, History and criticism, Operas, Chinese, Prostitutes, Theater, Women entertainers, Women musicians