This spake Zarathustra in article about goddess (7)
I believe the answer is:
avestan
'this spake zarathustra' is the definition.
(ancient language spoken by the prophet Zarathustra)
'article about goddess' is the wordplay.
'article' becomes 'an' (indefinite article).
'about' means one lot of letters goes inside another.
'goddess' becomes 'vesta' (I have seen 'Roman goddess ' mean 'vesta' so perhaps 'goddess' could also mean 'vesta'**).
'an' going around 'vesta' is 'AVESTAN'.
'in' is the link.
(Other definitions for avestan that I've seen before include "connected with sacred writings" , "Thus spake Zarathustra" , "relating to ancient Iranian language" .)