Over the past 15-20 years, Sergei Rachmaninoff's All-Night Vigil (a.k.a. "Vespers"), opus 37, and especially the 6th movement, "Rejoice, O Virgin,"have achieved a solid place in the repertoire of non-Russian choirs. Much lesser-known is Rachmaninoff's Liturgy of St. John Chrysostom, opus 31, which, besides being a major full-length work on its own, contains more than several eminently excerptable numbers within it. One of the most delightful of these is another hymn to the Virgin Mary-"It is truly fitting,"which, like its Marian counterpart from the Vespers, begins subtly and gently, but then builds to one of the most glorious climaxes within the choral miniature genre.