It is not a traditional church choir, in that they don’t have a ‘slot’ in the Sunday service when they sing while everyone else listens. It is predominantly an outreach ministry, involved in evangelism campaigns of various sorts.
The choice of songs is all-important, not only from the musical perspective, but in terms of getting the message of salvation to the people. There are many who will not come to church or attend outreach meetings, but who will listen to a choir.