This week the choir sings two anthems — the first, “Kyrie Eleison,” is an arrangement by David Angerman of a song by Keith Getty and Stuart Townend. Getty, from northern Ireland, and Townend, from England, frequently collaborate in writing modern hymns that have found acceptance in a wide spectrum of churches on both sides of the Atlantic. In the 11:00 service, this song will function as the confession of sin. The second anthem, “Christ has no body but yours,” by Bob Chilcott, was commissioned from the composer directly by Westminster. Chilcott, an English composer who sang with the choir of King’s College, Cambridge, both as a boy and as a university student, and was a member of the King’s Singers for twelve years, completed the anthem in the fall of 2015, and it was premiered at Westminster shortly thereafter.