When the people grumbled for bread, Moses's reply, as Targum Pseudo-Jonathan renders it, is a lesson in chain-of-command theology: By this you shall know, when the Lord prepareth you at evening flesh to eat, and in the morning bread to satisfy, that your complainings wherewith you complain against Him are heard before the Lord. And we, what are we accounted? Your complaints are not against us, but against the Word of the Lord.
The Targum uses its characteristic phrase memra d'Adonai, the Word of the Lord. Moses is not claiming that he and Aaron are beyond reproach. He is making a more subtle point: when you complain about the leadership God has appointed, you are, whether you know it or not, complaining about the One who appointed them.
"And we, what are we accounted?" The Aramaic ma chashvin means, literally, "of what reckoning are we?" Moses is emptying himself. He and Aaron are the messengers, not the principals. Shoot the messenger, the Targum implies, and your arrow still lands where you aimed it: at the sender.
This is a doctrine that the <a href='/categories/midrash-aggadah.html'>rabbinic tradition</a> returns to often. A leader who represents the divine Will can absorb criticism gracefully only if he remembers that the criticism was not really meant for him. A leader who forgets this grows defensive, proud, and eventually tyrannical. Moses's greatness, in the <a href='/texts/bamidbar-rabbah-12-11.html'>midrashic reading</a>, is precisely that he never confused his role with himself.
The Maggid's takeaway: if you are in a position of service, study this line until you can say it. What are we accounted? It is the only sentence that keeps you from breaking under the weight of other people's frustrations. Your work is not to absorb their anger. It is to forward it, honestly, to the One who actually sent you.