I guess there's no way of tracing something like this back.

Anyway when I read this in context of
what African-Americans are saying, writing, or posting online,
it's all about standing up to a challenge.

There is a subtext of:
The fever is a challenge that no tea will cure;
don't offer me tea if it won't cure the fever in the first place.

In this day and age, whether speaking of Aretha Franklin,
Paul Robeson, or one of the speakers at the Aretha Franklin service,
when this figure of speech is said,
it's about a statement in which the speaker did not beat about the bush
but said what was to be said even though it might give offense.

I guess this figure of speech has got layers to it.