The most common and most likely answer to this crossword clue is the 6 letter word CREDOS
I've seen this crossword clue in The Sunday Telegraph
C
R
E
D
O
S
More clues leading to the result CREDOS
- We believe these are left in lettuce
- Statements of belief taken to heart by the old
- Greek island retaining leftist systems of belief
- Religious education included in Conservative party’s statements of belief
- Company's embracing communist statements of belief
- Sets of opinions society rejected, socialist getting squashed
- Firm with section holding communist beliefs
Buddy explains!

The straight part
We know that "statements of belief" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case statements of belief = credos.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 CREDOS mean?
CREDOS noun- A belief system.
- The liturgical creed (usually the Nicene Creed), or a musical arrangement of it for use in church services.