Astrologer is to join group of believers in a few weeks (9)
I believe the answer is:
occultist
'astrologer' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'is to join group of believers in a few weeks' is the wordplay.
I cannot really see how this works, but
'is' is found in the answer.
'of' could be 'o' and 'o' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for occultist that I've seen before include "Supernatural believer" , "black artist" .)