The Quran's origins as an oral text in which recitation and intonation were of utmost importance, and its style of interweaving revelations from various periods into its sections, are its greatest influences on literature and poetry, according to the Encyclopaedia Britannica. In addition, because the Quran was written in Arabic, the Arabic language became the most important means of written expression in Islamic literature.
Since the beginning of Islam, believers from around the world have learned Arabic for both prayer and literary expression because the revelations of God in the Quran were written in Arabic. Among the first literary works attempted after the Quran was an intense effort by historians and other literary figures to compile the sayings and deeds of the Prophet Muhammad. These were anthologized in two collections called the Sahih. Later, besides the biographies, histories and fictional works written by Arab authors, literary works from foreign Islamic authors were translated into classical Arabic.
Following the writing of the Quran, the classic forms of Arabic poetry were adapted to extol Islam and its rulers. One such form was the panegyric, which praised important personages such as caliphs, theologians and philosophers. Another was the lampoon, which mocked and shamed enemies. A third was the elegy, which honored the dead. Though these literary forms existed before the advent of Islam, the revelation and transmission of the Quran changed the form and content of their expression.