Religious traveller, foreign character, large and stern (7)
I believe the answer is:
pilgrim
'religious traveller' is the definition.
(someone travelling on pilgrimage)
'foreign character large and stern' is the wordplay.
'foreign character' becomes 'pi' (Greek letter).
'large' becomes 'L' (eg in clothes sizes).
'and' means one lot of letters go next to another.
'stern' becomes 'grim' (synonyms).
'pi'+'l'+'grim'='PILGRIM'
(Other definitions for pilgrim that I've seen before include "One journeying to shrine etc" , "Christian, say" , "One on journey to shrine" , "Wanderer" , "Mecca visitor" .)