Saint's given foreign church prominence (8)
I believe the answer is:
salience
'prominence' is the definition.
(salience is a kind of prominence)
'saint's given foreign church' is the wordplay.
'saint' becomes 's'.
'given' means one lot of letters go next to another.
'foreign' becomes 'alien' ('alien' can be a synonym of 'foreign').
'church' becomes 'ce' (abbreviation for Church of England).
's'+'alien'+'ce'='SALIENCE'
(Other definitions for salience that I've seen before include "Condition of being most noticeable or important" , "Importance" , "Outstanding quality" .)