This is not a powerful magic. The main reason for being able to compete with Voldemort is the wand.
For the first time and the last time in the Goblet of Fire, both Voldemort's wand core and Harry's wand core came from the feather of Dumbledore's phoenix fox, and they were twin cores, so the flashback spell happened (even Dumbledore couldn't explain how it happened). In fact, Harry didn't defeat Voldemort at all, but the ghost in the flashback spell bought him time.
The second time was a decisive battle. Voldemort used an elder wand, which was taken from Dumbledore's grave. The wand changed hands to see who defeated him. From Half-Blood Prince, we can know that Dumbledore's wand was actually defeated by Malfoy's magic, while in Deathly Hallows, Harry defeated Malfoy and took the wand from him (though it was not the Elder's wand), so the real owner of the Elder's wand was Harry. When he killed you with his weapon and Voldemort killed him with Abada, the Elder Wand didn't want to hurt his real master, so Voldemort's Abada was disarmed by Harry.