From about the end of the 4th cent., Scriptural readings were recited to musical tones in church; the Gospel narratives of the Passion were thus recited in Holy Week. The characters were early differentiated by changes of pitch, and by the 13th cent. at the latest this was emphasized by dividing the narrative between three or more singers; from the 15th cent. parts or all began to be composed polyphonically. From the end of the 17th cent. lyric poems were sung in comment and chorales were added to be sung by the congregation; an orchestra was also introduced. J. S. Bach excelled in this oratorio type of Passion. Major 20th-cent. settings include the St Luke Passion of Krzysztof Penderecki (1966) and the St John Passion of Arvo Pärt (1982).