 The word first occurs in the chronicle (with reference to examples of 1228 and 1238) of Nicolas Trivetus, but later it came to mean only homiletic exposition, and thus became synonymous with the homily in distinction from the thematic sermon.Finally, after the middle of the fourteenth century, it was applied to an annual cycle of homilies.From the time of Martin Luther, who published the first part of his postil under the title "Enarrationes epistolarum et evangeliorum quas postillas vocant" (Wittenberg, 1521), every annual cycle of sermons on the lessons, whether consisting of homilies or formal sermons, is termed a "postil".