Nocturnal horseman always features in teaching of Scripture (6)
I believe the answer is:
revere
'teaching of scripture' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'nocturnal horseman always features in' is the wordplay.
'nocturnal horseman' becomes 're' (I can't explain this - if you can you should give a lot more credence to this answer).
'always' becomes 'ever' (synonyms).
'features in' indicates putting letters inside.
're' enclosing 'ever' is 'REVERE'.
Can you help me to learn more?
(Other definitions for revere that I've seen before include "Show great respect for" , "Woven fabric" , "Paul -, US revolutionary patriot" , "Hold in very high regard" , "Idolise, venerate" .)