The Iran nuclear negotiations. Photo: Screenshot from YouTube.

A roaring stadium is packed to capacity. Not Ohio State vs. Michigan, but the kind of brutal, life-and-death clash that occurred 2,000 years ago – in the Colosseum. The spectators have worked themselves into a frenzy, gleefully anticipating a menacing bull facing off against a condemned Jewish slave. The gladiatorial combat provides cheap entertainment for the bloodthirsty masses, who know that the slave’s slightest miscalculation will cost him his life.

In a Talmudic passage concerning our recommended conduct at such a time, one group of rabbis rules that a Jew is forbidden to enter the stadium because that individual’s attendance is tantamount to being an accessory to murder. The Jew’s patronage is supporting bloodshed.

But one of our sages, Rav Nosson, permits visiting the stadium because by ardently shouting and pleading, one moral person might be able to rescue a fallen gladiator. In fact, this mitzvah is so urgent that the person should go to the stadium even on Shabbat.

Although Rav Nosson’s perspective is only one opinion, the underlying principle that he espouses is unanimously agreed upon, and so, in a sense, he has demonstrated the import of his idea. He alone disagreed, and he turned a tide of thought.

So picture this scene.  A lone and righteous Jew in a stadium as all the people around him are callously carried away by a lust for blood. All thumbs are pointing down, condemning an innocent slave to death, except for this man’s thumbs, pointing to the heavens. Might he prevail? Perhaps not, but perhaps yes. Nevertheless, his presence and his voice are imperative. Rav Nosson believed that one moral voice can make an extraordinary difference.

The Lubavitcher Rebbe, of blessed memory, expressed himself similarly. Just as scientific theory says a butterfly’s wings can affect the weather on the other side of the world, the Rebbe instructed that the power of good deeds are as far-reaching. At the same time, however, the Rebbe warned that a nuclear missile on one side of the world can have devastating effects across the globe just by the dispassionate press of a button.

This week that specter loomed closer with the Iran nuclear deal. We need to use our voices to rail against the deal’s ratification in Congress, even if at times we feel we are the lone voice of reason in the stadium.

And beyond contacting our representatives in government and expressing our point of view in the media, we can light Shabbat candles, put on tefillin, and perform other mitzvot. God is always listening.

So how loud is one voice? Rav Nosson might respond that the power of one person’s voice, when it is pointing others toward the light, is immeasurable. This is a time for each of us to shout.

Rabbi Areyah Kaltmann is Executive director of Chabad of Columbus, Ohio.