Your question is too general to provide an exact answer. However in times past the language of religion was "Latin" and it is likely that if by "sacred music" you mean sung chants, then these would be in Latin.
No, sacred music is not always liturgical music, although it often is.
nationalistic music
Chopin wrote secular music. All of it is for or at least involves his instrument, the piano. He wrote no sacred music at all.
Sacred. The whole thing is about Jesus Christ.
Sacred song is used for worship or religious purposes. Secular song is common, everyday music.
sacred music is music used in churches, they are called hymns and psalms
the sacred book of buddhism is called the tipitaka and its writen in the language pali.
No, sacred music is not always liturgical music, although it often is.
The sacred writings in a whole is called the TaNaKh which stands for Torah, Nevi'im and Ketuvim. It is written in the Jewish language called Hebrew, except for the books Ezra, Nehemiah, Daniel which are written in Aramaic.
World Sacred Music Festival was created in 1994.
Possible anwers would include, but not be limited to a: hymn, spiritual, anthem, canitcle, carol, chant, chorale, doxology, processional, psalm. and/or requiem.
Sacred music is played in churches and meditation rooms. This is music that is to be revered and not taken for granted. Hymns are sacred music.
The sacred language of Hinduism is Sanskrit.
nationalistic music
Chopin wrote secular music. All of it is for or at least involves his instrument, the piano. He wrote no sacred music at all.
The holy language for Jews is Hebrew.
The Sikh's sacred language is Gurmukhi, which is a script used to write Punjabi language. The Guru Granth Sahib, the central religious scripture of Sikhism, is written in Gurmukhi.