Simply quoting someone on a subject achieves little toward building your own scholarly reputation. In many cases, the choice to paraphrase rather than quote demonstrates your grasp of the subject matter. It also enhances your credibility as both a critical reader and thinker.
Being able to paraphrase accurately demonstrates that you respect the contributions made by others while showcasing your own skill as a writer. This is especially useful when you want to point out specific details or information bearing directly on your argument or, when you wish to reference an opposing idea.
As with summarizing and quoting, whenever you restate someone else's words, thoughts or points of view you must document the source.