Altar covering in the flat’s modified to hide a raised gate (7)
I believe the answer is:
frontal
'altar covering' is the definition.
(I've seen this before)
'flat's modified to hide a raised gate' is the wordplay.
'modified' indicates an anagram.
'to hide' is an insertion indicator.
'a raised gate' becomes 'ron' (I can't justify this - if you can you should believe this answer much more).
'flat' is an anagram of 'ftal'.
'ftal' enclosing 'ron' is 'FRONTAL'.
'in the' is the link.
Can you help me to learn more?
(Other definitions for frontal that I've seen before include "Decorative church item" , "Direct and forceful" , "altar covering" , "Directly approaching" , "Altar hanging" .)