In Chaucer the sentiment it embodies is satirical:--

"For whan we may not don, than wol we speken,

Yet in our ashen cold is fire yreken."

In Gray, on the other hand, it is the moralist who solemnly declares:

"E'en from the tomb the voice of nature cries,

E'en in our ashes live their wonted fires."

But the coincidence cannot surely be accidental.