The Gloria in E flat major (1822) is Mendelssohns first sacred work for a full-scale vocal and instrumental setting. The score vividly illustrates how the entire musical concept originated on the basis of the vocal parts. A number of passages are entrusted to the vocal parts, which proves to be an effective means of contrast. Mendelssohn clearly made an effort to give the wind parts independent passages and to make the most of their tone colours.
(from the Preface)