It's right for an amended clause to be non-religious (7)
I believe the answer is:
secular
'be non-religious' is the definition.
(I've seen this before)
'it's right for an amended clause' is the wordplay.
'it's right' becomes 'r' (common abbreviation).
'for' says to put letters next to each other (I've seen this in other clues).
'an amended' is an anagram indicator.
'clause' is an anagram of 'secula'.
'r' put after 'secula' is 'SECULAR'.
'to' acts as a link.
(Other definitions for secular that I've seen before include "Clear us, not being involved in religion" , "Profane" , "without religion" , "Concerning the laity" , "Not connected with religion" .)