Practice : the actual application or use of an idea, belief, or method, as opposed to theories relating to it. Sermon : a talk on a religious or moral subject, especially one given during a church service and based on a passage from the Bible. Note : a brief record of points or ideas written down as an aid to memory. Letter : a character representing one or more of the sounds used in speech; any of the symbols of an alphabet. Epistle : a letter.