After Bach had composed the majority of his cantatas in the 1720s, he devoted himself increasingly to large-scale oratorical works in the 1730s. He began with the composition of the Mass in B Minor and reworked the St Matthew and St John Passions. At the turn of the year 1734/35 he performed the Christmas Oratorio for the first time. The six parts sounded on six consecutive Sundays and feast days alternately in Nikolai Church and Thomas Church in Leipzig.