Hersh Goldberg-Polin’s mother, Rachel, spoke directly to her slain son at his funeral Monday, saying she had been "absolutely certain that you were coming home to us alive. But it was not to be."

"Now I no longer have to worry about you. I know you are no longer in danger," she said. "But now my worry shifts to us. ... How do we live the rest of our life without you?"

Rachel Goldberg-Polin said she had always dreamed of what kind of man her 23-year-old son would grow up to be, but now he will always stay her energetic, kind, patient, funny and pensive "sweet boy."

"If there was something we could’ve done to save you and I didn’t think of it, I beg your forgiveness," she said to her son, days after his body and the body of five other hostages were recovered in Gaza.

She also asked for her son’s help "as we transform our hope into grief in this new, unknown brand of pain."

"I beg of you, Hersh, please do what you can … help shower us with healing and resilience. Help us to rise again," she said.

She said she hopes one day that their family -- including Hersh’s dad and two sisters -- will "hear laughter and turn around -- and see it’s us and were OK."

Through tears, the grieving mom begged her friends to help the family through this "sickening new chapter," pleading, "please don’t leave us now."

To her son, she said, "Finally, you're free. ... I love you and I will miss you every single day for the rest of my life."

Hersh Goldberg-Polin was curious, self-assured and a deep, independent thinker, his dad, Jon Polin, said at his funeral on Monday.

The 23-year-old, who was found dead in Gaza this weekend, was "always seeking to understand the other, and always with dignity and respect," Polin said.

"Hersh, we failed you. We all failed you,” Polin said with a "332" on his shirt, marking how many days his son was held hostage. "You would not have failed you. You would’ve pushed harder for justice … to bridge differences. … What you would be pushing for now is to ensure your death … [and the others’ deaths are] not in vain."

"Maybe, just maybe, your death ... is the fuel that will bring home the remaining 101 hostages," Polin said.

"You have become a global symbol of bringing improvement to our world," he said.

"The 23 years of life that we had with you were a blessing. We now will work to make your legacy a similar blessing," he said.

A funeral procession is underway in Jerusalem for slain Israeli-American hostage Hersh Goldberg-Polin. The 23-year-old was one of six murdered hostages recovered this weekend.

The Israeli Ministry of Health said the six hostages were killed “in a number of short-range shots” between Thursday and Friday morning.

The funeral comes one day after thousands of people took to the streets of Tel Aviv to protest the deaths of the six hostages.

More than 1,000 people have gathered in the northern Israeli city of Tel Aviv for continued anti-government protests, demanding that Prime Minister Benjamin Netanyahu conclude a cease-fire and hostage-release deal with Hamas.

Other marches are taking place elsewhere in Israel. A general strike -- called by Histadrut, Israel's largest trade union -- also began on Monday morning in protest of the government's failure to free those still held hostage inside Gaza.

Police reported violent clashes with anti-government protesters in Tel Aviv on Sunday night, saying officers had arrested 29 people.

The current wave of demonstrations was sparked by the recovery of the bodies of six of Hamas' hostages from a tunnel in the southern Gaza Strip on Saturday.

-ABC News' Joe Simonetti and David Brennan