A very good person protecting you up to now (2,3)
I believe the answer is:
as yet
'up to now' is the definition.
(both can mean until the present time)
'a very good person protecting you' is the wordplay.
'very good person' becomes 'st' (short for saint).
'protecting' indicates putting letters inside (inserted letters are held or protected).
'you' becomes 'ye' (historical version of 'you').
'st' enclosing 'ye' is 'syet'.
'a'+'syet'='AS YET'
(Other definitions for as yet that I've seen before include "Up till now" , "Thus far" , "Up to this point in time" .)