Hell Bent (S9 E12) is the most powerful episode of Doctor Who.

Past, present and future are all brought together in one explosion of pure Doctor-ness.

The Doctor never speaks a word for the first 10 minutes of his story about what happened on Gallifrey.
Then, his first words of the episode are “Get off my planet”

Prior to that encounter with the president, the President was talking to the General. The General suggests actually talking to the Doctor.
Rassilon responds “Words are his weapons.” and the General comes back with “When did they stop being ours?”

Finally, President Rassilon deems to go to the barn himself. That is when the Doctor first speaks and tells him to get off my planet.
Then Rassilon orders him to be shot. All ten hardened warriors miss. Rassilon grabs one and asks how it was possible that everyone missed. The solder responded:

“There was a saying, sir, in the Time War. The first thing you will notice about the Doctor of War is he’s unarmed. For many, it’s also the last.”

The solder then walks forward, drops his rifle and crosses the line to stand next to the Doctor and tells him “I was at Skull Moon, sir.”
By the end of the scene, all of the solders are standing with the Doctor, including the General.

This is powerful to me because I am childlike and believe in good over evil. A war hero is never shot down in cold blood for not doing anything wrong. The Doctor saved Gallifrey and so many people (the second time ’round).

This is the best part of Doctor Who. We only really see the Doctor’s story, but there are so many people affected by what the Doctor does.