Tension as holy person drops from heavens (6)
I believe the answer is:
strain
'tension' is the definition.
('strain' can be a synonym of 'tension')
'holy person drops from heavens' is the wordplay.
'holy person' becomes 'st' (I've seen this in other clues).
'drops from heavens' becomes 'rain'.
'st'+'rain'='STRAIN'
'as' acts as a link.
(Other definitions for strain that I've seen before include "Violent effort" , "Screen" , "Pass through a sieve" , "Try too hard" , "Overtax; tension" .)