For Two Violins, opt. Cello, and Organ. Mozart wrote seventeen Church Sonatas (sonata da chiesa), also known "Epistle Sonatas" between 1772 and 1780. These are short single-movement pieces intended to be played during a celebration of the Mass between the Epistle and the Gospel. This is No. 1 in E-flat. Shortly after Mozart left Salzburg, the Archbishop mandated that an appropriate choral motet or congregational hymn be sung at that point in the liturgy, and the "Epistle Sonata" fell into disuse. Here at SJMP, we're all for bringing it back!