Although István Beythe (1532-1612) is usually remembered for his botanical works, his main achievement is his four-part sermon collection (Németújvár, 1584). The first volume contains the Sunday gospels, the second the apostolic epistles he based his lessons on, the third includes excerpts from the Gospel used on feast days of the saints, and the fourth the explanation of the epistles dedicated to the main holidays. My study is about the genre and structural characteristics of these writings, with special emphasis on the denominational lessons of the book on the feasts of the saints.