Amma / Mata Amritanandamayi:

..."Service is also a form of sadhana. If you claim that you have attained

perfection after doing sadhana sitting in a certain place, Amma will not
accept that. Getting out into the world and doing service is very much a
part of sadhana. If we want to eliminate the enemies that lurk in the
innermost depths of the heart, we have to serve the world. Only then will we be
able to tell how effective our meditation has been. Only when someone gets
angry with us, will we know whether we still have anger in us."...