Passion of revolutionary no one's welcoming to Germany (8)
I believe the answer is:
devotion
'passion' is the definition.
(thesaurus)
'revolutionary no one's welcoming to germany' is the wordplay.
'revolutionary' says the letters should be written in reverse.
'one's' becomes 'ive' ('one has' can mean 'I have').
'welcoming' indicates putting letters inside (in sense of 'inviting in').
'germany' becomes 'd' (vehicle registration code for Deutschland).
'no'+'ive'='noive'
'noive' placed around 'to' is 'noitove'.
'noitove'+'d'='noitoved'
'noitoved' written backwards gives 'DEVOTION'.
'of' is the link.
(Other definitions for devotion that I've seen before include "Dedication" , "Strong emotional attachment - void note (anag)" , "Religious zeal" , "Feelings of ardent love" , "Intense loyalty" .)