Mark Chapter 14 Verse 7 is definiteky one of those verses where a knowledge of Greek helps.
Pantote gar tous ptookhous ekhete meth' heautoon
kai hotan theleete dunasthe autois eu poieesai,
eme de ou pantote ekhete
I want to draw your attention to the words hotan theleete dunasthe !
whenever you will / wish want to note the SUBJUNCTIVE PRESENT
then the Middle of dunamai ... most translations use can or may but this is a bit weak
dunamai I am able I have the power to do something
whenever you are willing to
you have the power or possiblity to do good
some of us have the desire and not the power or vice versa
ideally we would have both ?