Scripture lessons get writer mature (5)
I believe the answer is:
ripen
'mature' is the definition.
(to ripen is to mature)
'scripture lessons get writer' is the wordplay.
I cannot quite understand how this works, but
'scripture' could be 'ri' (I've seen this in other clues) and 'ri' is found in the answer.
'writer' could be 'pen' (something which writes) and 'pen' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for ripen that I've seen before include "Become ready for eating" , "Come to fruition" , "Grow older" , "Grow to maturity like fruit" , "Become mature" .)