Six years ago, our son spent his gap year on a program in Israel. He went off for a year of study and adventure. He couldn’t wait to immerse himself in Israeli life, speak Hebrew, live on Jewish time. We visited him after a couple of months and marveled at how much he’d grown up, how independent he was. In May, our happy-go-lucky son, unmistakably more mature, returned home to us.

Returned home to us.

I did not know Ezra Schwartz and I don’t know his parents, but the horror of what happened to their son, murdered by a Palestinian terrorist, will not leave me.

Every parent who has ever waved goodbye to a child heading to Israel has the same worry in the back of their mind. But one manages that fear by acknowledging that the odds of American kids on Israel programs becoming victims of terrorism are exceedingly low.

Only on a random sleepless night, when unthinkable thoughts come unbidden, might you dare to imagine what happened to Ezra Schwartz. That a barbarian, lusting for Jewish blood, encounters your child and murders him.

The Schwartzs are now living the nightmare of every parent. Their shock and grief are beyond measure. An ocean of loss rolls toward an unseen horizon, encompassing everyone who knew Ezra and even those who didn’t, but for whom this all hits too close to home. This is a kid who went to Jewish day school and worked at Jewish summer camps. A kid you’d see playing basketball at the JCC. You look at his picture and he looks familiar. Like every teenage boy I ever taught. Like our sons, like their friends. It Is impossible to look away.

Saturday night hundreds gathered at Ben Gurion airport to say goodbye to Ezra, as his coffin was loaded onto the plane that would return him to his family. The video shows his heartbroken friends, draped in Israeli flags, arm in arm, saluting Ezra with a stirring and mournful singing of “Hatikvah.”

Please do not use the word “tragedy” to describe what happened to Ezra Schwartz. If an eighteen year old contracts cancer, and despite the best efforts of his doctors, he dies, that is a tragedy. If an eighteen year old loses control of his car on an icy road and dies, that is a tragedy. When an eighteen year old is murdered by a savage who believes that Jews don’t deserve to live, that is an atrocity, an abomination. Words are all we have. Let’s use them precisely.

An eighteen-year-old young man is all raw potential and bundled dreams. In an instant the terrorist’s bullet obliterated all that was yet to be. What exactly was lost? The answer is found in Genesis, in the story of the first murder. God cries out to Cain: “What have you done? The blood of your brother cries out to me from the earth.” However, the original Hebrew is “damei achicha” — the bloods of your brother — and this distinction is lost in translation to English. God mourns not only the loss of the murdered person, but all the descendants — the bloods — that would have come from him, and now they never will.

The bloods of Ezra Schwartz cry out to God and to all of us, while over a dark and quiet ocean, his lifeless body was carried home.