A prayer song, performed by the
choir and congregation at church. Chorales
often became so well known that they turned into folk songs. Bach
was one of the famous choral writers;
he added his chorales accompaniment; overtures
(an opening movement) or interludes
he played on the organ.
Apart from original chorales he wrote himself, he arranged hundreds of
the chorales that were known in his time, and added voices to some. Bach
also introduced a concluding movement to his cantatas
in which he deployed a known choral,
thus letting the community participate. The choral melody is usually given
by the tenor,
and other voices accompany in harmony.