Among the doubts about the Holy Qur’an is the claim that some Qur’anic words-ending diacritics contradict the rules of Arabic literature but according to the theory of foregrounding, this kind of distinction of diacritical signs is not only a defect but one of the aspects of the beauty and rhetoric of the Holy Qur’an. Relying on exegeses, this analytical-descriptive study aimed to investigate the role of changing the style of words-ending diacritics and diacritical letters of the Holy Qur’an based on the theory of Geoffrey Leach, the English linguist. He considers the basis of foregrounding deviations from linguistic norms, which take two forms of "unexpected irregularity", and "unexpected regularity" or parallelism. The findings of this research indicate that the Holy Qur’an, by distinguishing the diacritics in some words, creates a kind of pause in speech and highlights it, and thus conveys the desired meaning to the audience. Such foregrounding in the Holy Qur’an occurs with respect to unexpected irregularity and syntactic deviation in the forms of conjunction and apposition by changing the diacritics of nouns and verbs for purposes such as praise, expression of surprise, and so on. Furthermore, unexpected regularity occurs by simulating an unnunated noun with a nunated one to create verbal musicality and rhythm and for purposes such as expressing greatness and surprise.