This term has a special meaning in 4th Way and QFS discourse. Gurdjieff originally wrote that man cannot do. There are many reasons, from the metaphysical to the psychological for why man cannot do.
Things happen, man does not do things. In exterior terms, plenty can happen through a person, but this happening is like the weather: Sometimes it rains, sometimes it freezes, sometimes it thaws, sometimes there is sunshine. Power in the sense of power over others does not enable man to do.
Man can only react, he cannot act. In order to be able to act, he would have to possess a consistent I. Sometimes one I wants to do, then another does not want to, yet a third does not care and forgets the whole issue. Man spends his life in sleep.
In terms of external reaction, Often the most minimal outside causes provoke the greatest and most violent reactions. This is not doing, this is mechanically reacting. Man can write libraries worth of speculations, be a slave to fiery passions, gamble his life away, all this without doing. Something does through the man but this is not him.
Doing involves a degree of free will. A reaction machine cannot do, a locomotive or motor car or airplane cannot do. Man may have the seed of free will and through cultivating this, along with being, something that was not previously even on the map of possibilities may become actualized.
In order to do, one must have an aim and one must have internal consistency, i.e. being. Doing and being may form a mutually reinforcing cycle.
Doing involves going against the flow of habit. Doing as we use the word implies a choice in favor of something higher than habit or compulsion or external necessity. Doing is doing in favor of one's destiny.
Doing, being, commitment, free will, knowledge and faith cannot be separated. Metaphysically, the doing which is done through faith in knowledge, in seeing the unseen, is the most significant, specially if this goes against habit. Reacting to something that absolutely requires reaction is not doing, it is merely reacting, it involves no free will or creative contribution to the universe. Doing in this sense involves an internal struggle, friction between yes and no, which holds the possibility for new crystallization. That which happens without conscious effort does not change one, it merely perpetuates habit.
Doing is not just any arduous, difficult or dangerous activity. It needs a higher aim, a creative purpose which is of service to an esoteric principle. Doing can well take place on the fully personal plane, and does not have to involve changing the world. Still, doing as intended here is a creative act, rooted in seeing and in having an aim and requiring struggle, faith and wakefulness.
Doing is not the same as pushing through an agenda or going to hell and back to get what one wants. Doing is a more open and interactive process, yet it involves making a stand and drawing a figurative circle around where one stands.
Goethe expresses these ideas as follows:
'Until one is committed, there is hesitancy. The chance to draw back, always ineffectiveness concerning all acts of initiative (and creation). There is one elemental truth, the ignorance of which kills countless ideas and splendid plans--- that the moment one definitely commits oneself, then Providence moves all. All sorts of things occur to help one that would never otherwise have occurred. A whole stream of events issue from the decision, raising in one's favor all manner of incidents and meetings and material assistance which no one could have dreamed would come his or her way.
Whatever you can do or dream, you can begin it. Boldness has genius, power and magic in it. Begin it now.'