Expelliarmus and backfiring

[potioncat]

No: HPFGUIDX 184614

 
> Carol adds:
> Just a quick note here. The master of Death is not the master of the
> Elder Wand but the legitimate owner/master of all three Deathly
> Hallows. Harry may have been, briefly, Master of Death while he wore
> the Cloak (inherited from James and rightly his), held the
> Resurrection Stone (which, unlike DD, he apparently had the right to
> use because he wasn't trying to bring his dead loved ones back to
> life, only to have their compnany before he joined them), and was
> (though he didn't know it yet) master of the Elder Wand, having
> disarmed Draco, the previous inadvertent master. 

Potioncat:
One point here. I thought anyone who recognised the Resurrection 
Stone could use it--presuming they knew how, or were lucky enough to 
work it out. Marvolo just thought it was a family heirloom and didn't 
know about its powers.

DD knew what the stone was and forgot for a moment what the ring was. 
It was the ring, not the stone that damaged his hand. I thought that 
later he determined it was better to avoid using the stone. In this 
case, choosing what was right over what was easy. 

When Harry uses the stone, he's using it to give himself strength to 
carry out his mission.