Walter Ong, Marcel Jousse, and other scholars of orality have listed features common to the verbal productions of oral societies. At the forefront of these features is rhythm. A physiological phenomenon rooted in human breathing patterns, speech rhythms are a mnemonic aid integral to orally based expression. For the predominantly oral societies of pre Islamic and early Islamic times, this meant that their artistic verbal productions were grounded in rhythmic patterns. However, the classical Arabic oration had functions that were different from the functions of the verbal productions of other societies. The rhythm of the Homeric epic, for example, was built around recurring epithets, a feature absent from Arabic orations. Moreover, the rhythm of the oration was grounded in a context different even than the context of the other verbal genres of Arabic literary production. Its production method was largely spontaneous, and its purpose was primarily to persuade. The differences in context lead to differences in mode of rhythm. So while Arabic poetry primarily used rhyme and meter, and the Qur'an assonance, the oration relied on parallelism to produce a rhythmic, and thus memorable, artistic piece. Parallelism in the classical Arabic oration teamed up with other acoustic, semantic, and syntactic features: audience engagement devices, vivid imagery, citation of sacred or traditional material, and dignified yet simple language. Together, these five features provided an aid to memorization, and simultaneously, through rhetorical means, they tacitly steered the audience to the speaker's point of view. Analysis of a sermon on piety attributed to Ali b. Abi Talib will demonstrate the aesthetic workings of the classical Arabic oration. To the goal of convincing the audience to prepare for the hereafter, Ali harnesses from within the five groups mentioned earlier several stylistic techniques of tacit persuasion: antithetical parallelism, repetition of key terms, application of emphatic structures, posing of rhetorical questions, and straightforward yet elevated vocabulary and syntax. Through a skillful usage of these devices, he delineates a clear contrast between this world and the next, today and tomorrow, good and evil, guidance and error.