What magic protected Harry at the Dursleys?

Dumbledore placed an ancient charm on Harry once he found him, which he explained in Order of the Phoenix. This used Lily’s sacrifice as a basis to protect Harry when he called a place of his mother’s blood – ie his aunt Petunia’s house – home.

Why does Harry have to go back to the Dursleys every year?

Harry had to return to Dursley’s every year before his seventeenth birthday because of an ancient charm that was placed on him by Dumbledore when he was bought to the Dursley’s doorstep. As long as he was in Petunia’s care, Voldemort couldn’t hurt him. She shared the blood with Lily and their blood became his refuge.

How is Harry protected from Voldemort?

Lily Potter sacrificed her life in order to protect her infant son, Harry from Lord Voldemort. This placed Harry under magical protection, so that when Voldemort cast the Killing Curse at Harry in turn, the spell backfired, leaving him unharmed (save for a lightning-shaped scar on his forehead) and Voldemort bodiless.

Was it Dumbledore’s charm or Lily’s that protected Harry all those years?

According to the answer here: Was it Dumbledore’s charm or Lily’s that protected Harry all those years?, Harry was only protected by his mother’s sacrifice because Dumbledore invoked the ancient magic created by Lily’s sacrifice.

Why didn’t Lily’s protective charm work on 4 Privet Drive?

The protective charm on 4 Privet Drive did not. Lily’s protection had several aspects to it. Primarily, it shielded the baby Harry from Voldemort’s Killing Curse. Once Dumbledore cast a specific charm, the protection was extended to Privet Drive for as long as Harry was a child and as long as he could call that place home.

Does Harry’s death protect him from Voldemort?

Actually, there is no evidence in the book that anybody would be protected by Harry’s death, except that Harry says so. The sequence is this: Voldemort was in the centre of the battle, and he was striking and smiting all within reach.

How did Harry know she could feel his heart beating?

Hands, softer than he had been expecting, touched Harry’s face, pulled back an eyelid, crept beneath his shirt, down to his chest and felt his heart. He could hear the woman’s fast breathing, her long hair tickled his face. He knew that she could feel the steady pounding of life against his ribs.