One offered to help with the Spanish for composer (6)
I believe the answer is:
handel
'composer' is the definition.
(George Frideric Handel)
'one offered to help with the spanish' is the wordplay.
'one offered to help' becomes 'hand' (as in lending a hand).
'with' is a charade indicator (letters next to each other).
'the spanish' becomes 'el' ('the' in Spanish).
'hand'+'el'='HANDEL'
'for' acts as a link.
(Other definitions for handel that I've seen before include "German composer, George Frederick (1685-1759)" , "German baroque composer" , "German-born composer to the ` `Messiah' '" , "British composer of German birth, the 'father of the oratorio'" , "German composer, lived in England" .)