This month, Jews around the world come together in synagogues, community centers, and schools to commemorate Kristallnacht—the night of broken glass. We do this to remember what happened on the fateful nights that marked the beginning of what would become the Holocaust.

In Hebrew, the word for “remember” is “zachor.” But zachor doesn’t just mean recalling the events of the past. Zachor means learning the lessons of the past. Zachor means putting those lessons into practice. And zachor means honoring those who live on in our memory.

As Holocaust survivor and Nobel Prize laureate Elie Wiesel once said, “For the dead and the living, we must bear witness.”

On Wednesday, Nov. 9, 1938, the Nazi SS paramilitary forces, aided by German civilians, unleashed a pogrom against the Jews of Berlin, Vienna, Prague, and cities across the heart of Europe. They dragged Torah scrolls through the streets; torched more than 1,000 synagogues; vandalized Jewish homes, businesses and cemeteries; and murdered nearly 100 Jews.

As fires raged and glass was shattered, local firefighters, policemen, and neighbors stood by and did nothing. During those two nights, as many as 30,000 Jewish men were arrested and deported to concentration camps. Those who were left were forced to wear a yellow star with the word “Jude”—Jew—sewn onto their clothing.

This pogrom specifically, and the Holocaust in general, could not have taken place without the preparation of hearts and minds of these people to tolerate the cruelty against their neighbors. Kristallnacht symbolized then, and now, how anti-Jewish legislation and anti-Semitic rhetoric lead to violence. It reminds us that the Holocaust began not with gas chambers, but with words. This lesson has important implications today.

What occurred on those nights in November was about more than broken glass. It was a warning. The rise of Nazi Germany had ushered in a new dark era of inhumanity and barbarity. The day after Kristallnacht, the New York Times declared, “No man can look on the scenes witnessed yesterday without shame for the degradation of his species.” Time magazine proclaimed, “The civilized world stands revolted by a bloody pogrom against a defenseless people.” And yet, the rest of the world did heartbreakingly little to stop what was already unfolding for European Jewry.

In the 70 years since the end of World War II and the liberation of the concentration camps, racial prejudice and violence still live on. Within living memory of the murder of 6 million European Jews, anti-Semitism has returned to the streets of Europe. The violence is new, but the targets are the same.

Just this year, Argentina, Hungary, Greece, France, Poland, and Russia all saw the vandalizing of Jewish cemeteries and memorials with swastikas and vile slogans.

In January, four Jews were killed in an attack on a kosher supermarket in Paris. In April, vandals in Copenhagen smashed the window of a kosherdeli and wrote the words “Jewish pig” on the wall. And in June, anti-Semitic profanities were painted on the gates of a London Jewish primary school.

In light of the ongoing violence we must ask ourselves: Have we truly followed the principle of zachor? Have we remembered the lessons of the past?

Remembering Kristallnacht means understanding that the demonization of a people leads to the dehumanization of a people, and finally, to the destruction of a people. Remembering Kristallnacht means ensuring that, in the face of evil against fellow human beings, it is never acceptable for silence to be an option, indifference a strategy, or “never again” a mere slogan.

Finally, remembering Kristallnacht means deciding whether we will be remembered by our descendants as protectors of peace and human rights, or as bystanders to the most grievous crimes against our humanity. We must all ask ourselves whether we are doing enough to raise our voices and take action against the increasing violence around the world that is fueled by hatred.

There is a stone that remains from the Great Synagogue in Munich that was set aflame the night of Kristallnacht. This stone represents one of the darkest times in human history, and the history of the Jewish people. If you look closely, you can still see the burn marks from that fateful night.  These markings of hatred and anti-Semitism are, in a very real sense, the cornerstone of the United Nations, which was established to “to save succeeding generations from the scourge of war.”

The State of Israel was founded with the same promise, to ensure that never again will the survival of the Jewish people be threatened.

It is our hope and prayer that the lessons from that terrible era are learned for the sake of all mankind.

Am Yisrael Chai. Long live the people of Israel.

Reprinted with author’s permission from JNS.org