God is love, ultimately providing boost (5)
I believe the answer is:
raise
'boost' is the definition.
(I know that boost is a more specific form of raise)
'god is love ultimately' is the wordplay.
'god' becomes 'Ra' (Egyptian god).
'ultimately' says to take the final letters.
The last letter of 'love' is 'e'.
'ra'+'is'+'e'='RAISE'
'providing' acts as a link.
(Other definitions for raise that I've seen before include "Hoist" , "cairn" , "To promote" , "What a poker player might do" , "Contact" .)