Rotem Mathias, 16, says his mother tried shielding him from the bullets with her body before she died.
"The terrorists shot open the door," Mathias recalled during an interview with ABC News. "They throw a grenade or something that exploded. The last thing my dad said is he lost his arm and then my mom died on top of me."
Mathias recalled the tragedy and how he hid under a bloodied cloth for hours on Saturday during the attack.
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"I just stopped my breathing, I lowered it down as much as I possibly could," Mathias told ABC News. "I didn't move. I was terrified. I didn't make any noise. And I prayed for any god -- I didn't really care which god -- I just prayed for a god that they won't find me."
His home was set on fire and he was forced to leave. He was later rescued by Israeli forces.
His older sister also hid during the attack but barricaded herself in a safe room to survive.
Meanwhile, the war, which has claimed at least 2,300 lives on both sides, is expected to escalate: Israeli Prime Minister Benjamin Netanyahu joined with a top political rival Wednesday to create a war-time Cabinet overseeing the fight to avenge Hamas' attack.
ABC News and the Associated Press contributed to this report.