It is among the terms that have received great attention in studies dealing with discourse analysis. This term has been transferred from the engineering field to the field of discourse analysis, like many mathematical and scientific terms that have been transferred to other fields.Some modern researchers have tried to establish the concept of parallelism through the Arab rhetorical heritage, and they pointed out that ancient Arab critics noticed many rhetorical forms that fall under the concept of parallelism and are closely related to it, such as: (inlay, inlay, proportionality, similarity, repetition, and incompleteness) The ancient Arab critics were fully aware of the feature of parallelism. They paid special attention to it.