The most common and most likely answer to this crossword clue is the 9 letter word FALDSTOOL
I've seen this crossword clue in Financial Times
F
A
L
D
S
T
O
O
L
Buddy explains!
The straight part
We know that "Item of church furniture" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case item of church furniture = faldstool.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FALDSTOOL mean?
FALDSTOOL noun- A portable, folding chair used by a bishop when away from his throne.
- Any similar stool used in a divine service (such as the coronation of a British monarch).