It's funny how language shapes our thinking. The word rest has a bias towards related words such as inactivity and being passive. Hard to change that now! Imagine a culture/language where we would say "time travel" instead of "rest"! It would completely change how we look at resting..
I need to go time travel a bit now :)
Latin writers from Cicero to Augustine understood the word in a very similar way. For example the poet Ovid once referred to his poetry as otia nostra (creations of our leisure). [2] In his case the leisure time was due to being banished from Rome to the little town of Tomi on the Black Sea.
[1] https://en.wikipedia.org/wiki/De_Otio
[2] https://www.loebclassics.com/view/ovid-tristia/1924/pb_LCL15...
Yes. We need to change "I need some rest" for "I need some introspection". I agree that is a change from "lazy" or "not-doing-anything" towards "profound" and "self-improvement".