Detachment is the beginning …

Detachment is the beginning of mastery, but for complete mastery there should be no reactions at all. When there is something within undisturbed by the reactions that means the inner being is free and master of itself, but it is not yet master of the whole nature. When it is master, it allows no wrong reactions—if any come they are at once repelled and shaken off, and finally none come at all.

Ref : Letters on Yoga Vol. III