“Although describing and explaining are distinguishable, they are also in an important sense inseparable. The descripitive and explanatory resources of language advance hand-in-hand."
These two kinds of discursive activity, one can be describing in a particular act and not explaining (and vice-versa).
Globally, they’re only intelligible in terms of their relation to each other.
The claim that matters: you couldn’t have an (autonomous discursive) language in use that had one and not the other.
The reason is at least that in order to describe something you have to place it in a space of implications (i.e. the above quote)