With the high altar, the choir represents the head of our divine redeemer.-in church achitecture, if you were to superimpose the body of jesus onto a diagram of the church, the head of christ fits in the sanctuary; the arms become the transepts; and the body and legs fill out the nave. the choir is another essential part of the nave. it is the place in the church set aside for those members of the congregation who are specially trained to lead the sung portion of the liturgy. for acoustical reasons, choirs are typically placed on one of the buildings axes. in many ancient churches the choir is made up of a series of stalls at the front part of the nave near the altar, but this was common only when choirs were made up exclusively of clergymen. the first church known to accommodate such a choir was san clemente in rome, when an enclosed choir (called the schola cantorum) was placed in the nave during the twelfth century. but monastery churches had introduced choir stalls nearly six hundred years before that, because chant has long been an important part of monastic prayer.