The most common and most likely answer to this crossword clue is the 3 plus 6 letter word LAY READER
I've seen this crossword clue in Independent
L
A
Y
R
E
A
D
E
R
More clues leading to the result LAY READER
- Boss drinking port who carries out some services
- Churchman responsible for poetry recital?
- Service man licensed by bishop to brew dreary ale
- Editorial about Scottish town preacher
- Minister’s assistant has written article about Scottish town
- Head describing Scottish town preacher
- Amateur working on Sunday‘s brew of a dryer ale
- Pioneer to secure Scottish port and volunteer for service?
- … serviceman who enjoys Macaulay?
- Church assistant and boss seen round outskirts of Scottish town
Buddy explains!

The straight part
We know that "Minister’s assistant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case minister’s assistant = lay reader.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.