He scored the vocal parts for four soloists: soprano, alto, tenor and bass. The choral writing is in four parts, and the work can be sung with just four singers, the so-called OVPP approach.
For the vocal roles, he allocated parts for a soprano, an alto, a tenor, and a bass soloist. The choral writing consists of four parts, and the work can be sung by only four individuals, referred to as the OVPP approach.