[byrneseyeview]

Rewriting would be something closer to:

The passages he copied were short descriptions of events in history. Repeating them word-for-word, like he did, would be considered plagiarism, but since they are a source for events he wasn't there to see, shouldn't he just reword them?

There's no point in doing that. It's better to quote verbatim with citations, and to write when there's something new to say. Historians can compile primary sources into a new document that adds something to the existing information; they don't curate documents, they narrate events.

[calambrac]

There's no allowance for style? If my source is dry and pedantic, and quoting would disrupt the flow of what I'm trying to say, it's really that grievous a sin to rewrite?