Piece of the church? (6)
I believe the answer is:
bishop
'piece' is the definition.
(I know that Bishop is a type of chess piece)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for bishop that I've seen before include "Board member" , "He wears the mitre and carries the crozier" , "Diagonal board mover" , "Powerful cleric" , "High-ranking clergyman" .)