Vice President Joe Biden gave a heartfelt speech on dealing with loss of a loved one to military families and friends at the annual TAPS National Military Survivor Seminar in 2012. Biden's son, Beau, died of brain cancer on Saturday after battling the disease for several years. (YouTube/Tragedy Assistance Program for Survivors)

Perhaps more than any other American politician, we have a sense of how Joe Biden processes grief.

The vice president, who is mourning the loss of his 46-year-old son, Beau, today, has lived through unimaginable tragedy. His first wife and 13-month-old-daughter, Naomi, died in a car crash just a few months after the 29-year-old was first elected to the U.S. Senate, in 1972. Beau, then 3, and Biden's other son, Hunter, then 2, were seriously injured.

In a candid 2012 speech to military families and friends who had lost a loved one in action, Biden spoke about the anger, crisis of faith and wounds that don't really ever heal.

"No parents should be pre-deceased by their sons or daughters," Biden said. "I, unfortunately, have that experience, too."

[Photos: The life of Beau Biden]

It's a moving speech worth watching in entirety. But here are some of the moments he shared about the agony of losing a loved one much too soon.

He first touched on the moment he got the phone call saying his wife and daughter had been in an accident.

"By the tone of the phone call, you just knew, didn't you? You knew when they walked up the path. You know when the call came, you knew. You just felt it in your bones. Something bad happened. And I knew. I don't know how I knew. But the call said my wife is dead, my daughter is dead, and I wasn't sure how my sons were going to make it."

The somber Biden drew claps and laughter from the crowd when he said how well-meaning people who had never lost a loved one just tend to say the wrong thing.

"I have to tell you. I used to resent people. They'd come up to me and say, 'Joe, I know how you feel.'" To claps and laughter, he continued: "I know, right? I knew they meant well. I knew they were genuine. But you knew they didn't have any damn idea."

Washington Post reporter David Fahrenthold, who was at the speech, said Biden appeared to transform from a vice president into a grief-stricken man.

"He hunched over, he looked down at his hands, he spoke at times haltingly and at times through clenched teeth," Fahrenthold wrote.

Biden shared how, after he found out that his wife and daughter had died, he understood how grief could push someone to suicide.

“For the first time in my life, I understood how someone could consciously decide to commit suicide. I realized someone could go out — and I probably shouldn't say this with the press here, but you're more important — I realized how someone could consciously decide to commit suicide. Not because they were deranged, not because they were nuts. Because they’d been to the top of the mountain, and they just knew in their heart they’d never get there again, that it was never going to get — never going to be that way ever again."

The self-described practicing Catholic also spoke about the profound anger, especially toward God, that gripped him in the days after his daughter and wife died.

"I was angry. Many I was angry. … I was a practicing Catholic at the time, but I was mad at God, oh man.  I remember being in the [Capitol] Rotunda walking through to get the plane to get home to identify — uh, anyway — and I remember looking up and saying, 'God.' I was talking to God myself: 'God, you can't be good. How can you be good?'"

Biden also talked about how years later he and his family struggled when Beau, who earned a Bronze Star when he deployed to Iraq in 2009, came home in one piece. A year after this speech, Beau would be diagnosed with brain cancer.

"Our son spent a year in Iraq. When he came home, it's going to sound strange to you, we felt almost a little guilty because he came home. Because there's so many funerals I've attended, so many bases I've visited. And you know, not all losses are equal. Not all losses are equal."

[Brain cancers like Beau Biden’s kill about 15,000 adults each year]

Biden warned military families that the initial feeling of loss never quite goes away.

"Just when you think you're going to make it, you're driving down the road and you pass a field and you see a flower, and it reminds you. Or you hear a tune on the radio. Or you just look up into the night and, you know, you think, 'Maybe I'm not going to make it, man.' Because you feel at that moment the way you felt the day you got the news."

But there is hope, Biden told the military family members in the audience.

"There will come a day, I promise you and your parents, as well, when the thought of your son or daughter or your husband or wife brings a smile to your lips before it brings a tear to your eye. It will happen. My prayer for you is that day will come sooner or later.. But the only thing I have more experience than you in is this: I’m telling you it will come.”

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