This summary is about five verses of the Gita (Gita 11.31–35). On Arjuna's journey this is the sixth stop.
The question is this: when the outcome is not in your hands, but you fear that if things go wrong the blame will be yours, what does "be an instrument" mean?
The answer in one sentence
Do your work with your whole mind, but give up the claim that you alone make the whole outcome. Being an instrument does not mean stepping back from action or from responsibility. The action is yours, but you are not the sole maker of the result.
Two things are taken from Arjuna: the claim of being the sole maker of the outcome, and the fear that grows from it. The action is not taken away.
The setting
Arjuna has been given the divine eye (Gita 11.8). At first the form looks glorious, and then it becomes terrible: a form with many fangs and blazing mouths, at the sight of which he has neither courage nor peace (Gita 11.23–25).
Then Arjuna sees the warriors of both sides rushing into the mouths of that form (Gita 11.26–30). So he asks: who are You?
The verses in order
Verse 11.31: Arjuna asks
Arjuna bows and asks: You of the fierce form, who are You? I cannot understand Your ways.
This is the question of a devotee sunk in fear. It holds no quarrel, only a cry to understand. Asking after bowing shows that trust is still there.
Verse 11.32: "I am Time"
The Lord says: I am Time, grown great, the destroyer of the worlds, and I am now gathering the worlds in. Even without you, the warriors on the other side will not remain.
The Lord gives His introduction not as one who fights but as time.
The words "even without you" loosen Arjuna's burden that these men will die by his hands.
This verse does not justify the war. It says only that time does not wait for Arjuna's decision.
Verse 11.33: "Arise, be merely an instrument"
The Lord says: arise, win glory, conquer your enemies and enjoy the kingdom. These have already been slain by Me. O Savyasachi, be merely an instrument.
"Savyasachi" means one who can shoot with both hands, that is, a skilled warrior. So the skill is yours, and still you are to be the means.
The word "merely" does the work. You are the means of action, but not its sole maker. One who takes himself as the sole maker carries the burden of every result, whether it is in his control or not. This is the very burden that was pressing on Arjuna.
The talk of glory and kingdom is the language of the second chapter (Gita 2.31–37), speaking to Arjuna in his own tongue. The high note of the Gita is not glory but equanimity.
Verse 11.34: Four names
The Lord says that Drona, Bhishma, Jayadratha, Karna and the other warriors have already been slain. Do not be troubled, fight, you will surely win.
The first names are those of Bhishma and Drona, before whom Arjuna had once laid down his arms (Gita 2.4). So the old fear is addressed by its name.
Care is needed here. These words were said to one warrior, about one particular war, within a teaching. They are not an order that applies to someone else.
Verse 11.35: Arjuna trembles
Sanjaya tells us that Arjuna, with folded hands, trembled, bowed again and again, and spoke once more in a voice choked with fear.
Hearing "fight", he did not rise with zeal. He bowed lower. Later he praises the Lord and asks for the old form back (Gita 11.45–46).
Arjuna's path in chapter 11
Through the chapter Arjuna's state passes through several stages.
First comes the wish to see, with trust and curiosity (Gita 11.1, Gita 11.3). Then the divine eye is given, and he is ready for the vision (Gita 11.8). Then the glorious form appears, and he is amazed (Gita 11.12, Gita 11.15–16).
After that the terrible form comes, and there is distress (Gita 11.23–25). Then the warriors are seen entering its mouths, and there is terror (Gita 11.26–30).
Then come the question and the answer, a cry to understand, and it is here that "be an instrument" is said (Gita 11.31–34). After that Arjuna trembles, in fear and humility (Gita 11.35).
Then he asks for the old form, with joy and fear together (Gita 11.45–46). When the gentle form brings reassurance, his mind becomes steady (Gita 11.49–51). And at the end the mark of the devotee is given: free of hatred and of attachment (Gita 11.55).
"Be merely an instrument" comes after the deepest fear and before the reassurance. It is said inside the fear, to help him cross it.
Where Arjuna was before
In the first chapter Arjuna says that killing these people would bring only sin (Gita 1.36), and he sinks down on the chariot, putting aside his bow (Gita 1.47). The feeling underneath was: if this happens, I will be its cause.
In the eleventh chapter the Lord says: you are not the only cause. These are two ends of one question. Before, Arjuna said, "I do not want to be the cause." Now the answer is, "You are not the only cause anyway." The middle way is the instrument.
What the word "Time" teaches
The second chapter says that death is certain for one who is born, and that one should not grieve over what cannot be avoided (Gita 2.27). The eighth chapter describes the coming and going of creation as like day and night (Gita 8.18–19).
Many things are in the hands of time. To carry them on one's shoulder is neither right nor possible. This is not laziness but right judgment. Put full effort into what is in your hands. What is in the hands of time, leave to time.
Fear and the Lord's answer
Arjuna's first fear is: who is this fierce form? The Lord's answer is: I am Time (Gita 11.32).
The second fear is: will these men die or be spared by my fighting or not fighting? The answer is: even without you they will not remain (Gita 11.32).
The third fear is: the burden of so great an outcome is on my head. The answer is: you are merely an instrument (Gita 11.33).
The fourth fear is: how can I fight before the revered Bhishma and Drona? The answer is: they are already slain, do not be troubled (Gita 11.34).
In this way each fear is taken up in its own form and one burden after another is lifted. It is less an order than an answer to fear.
Companion verses on the instrument-spirit
Several more supports for the same spirit are found in the Gita.
The second chapter says that the right is to the work and not to its fruit (Gita 2.47). Being an instrument is the vision behind this.
The third chapter says that actions are done by the qualities, and a mind confused by ego says, "I am the doer" (Gita 3.27). In the same chapter we are told to offer all actions and to fight after giving up hope, the sense of mine and the fever (Gita 3.30). That verse is closest to 11.33.
The fifth chapter says that one who offers his actions, like a lotus leaf, is not stained by wrong (Gita 5.10).
The eighteenth chapter gives five causes of action, and says that one who sees only the self as the doer does not see rightly (Gita 18.14–16). An instrument is one cause among many.
In the same chapter the Lord says: having thought it over fully, do as you wish (Gita 18.63). So being an instrument is not against choosing. And at the end comes Arjuna's decision: I will do as You say (Gita 18.73).
Four common misunderstandings
The first misunderstanding is: the Gita tells us to fight and kill. These words were said to one warrior, within a teaching, about one war. In the same chapter the devotee is described as free of hatred (Gita 11.55), the one who bears no ill will is dear to the Lord (Gita 12.13), and non-violence is counted among the divine qualities (Gita 16.2).
The second is: everyone is already slain, so what I do has no meaning. But the Lord asks for action, saying arise and fight, and He also gives the choice back (Gita 18.63). "Already" is the language of the height from which everything is seen at once.
The third is: I am an instrument, so I am not responsible. Escaping responsibility is not the Gita's teaching. The instrument is the mind that does its work with full sincerity and does not take the outcome as its own alone.
The fourth is: an instrument is a puppet. Arjuna asks, fears, trembles and in the end chooses. The Lord Himself gives back the right to choose (Gita 18.63).
In daily life
This spirit is useful in three situations.
When the work is shared, do your part with your whole mind, and do not sit and worry about the rest.
When a decision has come down from above and you have to pass it on, you are not its maker but its carrier. How you carry it, though, is yours.
And when the fruit of your effort depends on others, as in teaching or training, give your best and let the other person's hand remain his own (Gita 2.47).
One thing is common to all three: the action complete, the claim loose.
"I am only God's instrument": a check against misuse
It is possible to call one's own stubbornness "God's work". So the Gita offers four checks.
The first check: is the mind even, the same in victory and defeat? (Gita 2.38)
The second check: is the action offered, free from hope, sense of mine and fever? (Gita 3.30)
The third check: has the feeling of being the doer loosened? (Gita 3.27)
The fourth check: is there no hatred for anyone? (Gita 11.55, Gita 12.13)
An "instrument" who sits holding anger, possessiveness or hatred does not pass these checks. The claim is not proof in itself. Arjuna himself did not say it. He trembled, bowed and went on asking.
How the Lord handles fear
The Lord does not call fear wrong. He says: let there be no distress or confusion, and see that same form again with a fearless, happy mind (Gita 11.49).
The answer is not in words but in presence. He comes in the gentle form and reassures Arjuna (Gita 11.50). And only after the reassurance does Arjuna return to his usual state (Gita 11.51).
So the spirit of the instrument does not come by pressing fear down. It comes in front of fear, with support.
Questions people ask
Is the future already fixed? Verse 11.32 speaks from the view in which everything is seen at once. In the same vision the Lord says "arise, fight" (Gita 11.34), and later He gives the choice back (Gita 18.63). To make this a doctrine that everyone's future is fixed goes beyond the text.
Does responsibility end when one becomes an instrument? No. What goes is the ego of the doer and the sole burden of the outcome (Gita 3.27). The care and honesty of the action remain yours.
Why was the lure of a kingdom offered? It is speaking in Arjuna's own language (Gita 2.31–37), while the Gita's measure is equanimity. It is the language of the start of the teaching, not its last word.
There is no war in my life, so what do I learn? What is useful to all: do your work with your whole mind, and give up the feeling of being the sole maker of the outcome (Gita 3.30).
He was promised victory, so why did Arjuna tremble? The fear is not from the news of victory but from the grandeur of the vision (Gita 11.45–46). When the Lord returned to the gentle form, he became steady (Gita 11.49–51).
Explain it in thirty seconds
Seeing the fierce form of Time in the cosmic vision, Arjuna asks who the Lord is (Gita 11.31). The Lord says: I am Time, and even without you these warriors will not remain (Gita 11.32). So arise and be merely an instrument (Gita 11.33). What this lifts from Arjuna's shoulders is the claim of being the sole maker of the outcome, and the fear, not the action. Do your work with your whole mind, but do not carry the entire burden of the result alone. Being an instrument is not escaping responsibility, not being a puppet, and not calling one's stubbornness "God's work". In the end the choice remains Arjuna's own (Gita 18.63).