Arabic speakers recognized several established literary forms, including poetry, public address, letters, and dialogue. Qur’anic discourse is not simply an example of one of these forms. It presents a distinctive style in structure, impact, and the joining of themes.
Originality of style does not mean stuffing the text with unknown Arabic words. It refers to an expressive form that uses intelligible language yet is not merely an imitation of the available literary categories.
Application: a passage can unite direct address, question, reply, warning, and narrative without being adequately described as a poetic ode, a routine sermon, or a letter.