Blackfish: Kingslayer.
Jaime: Blackfish.
Blackfish: I assume you're here to fulfill the vow you gave my niece. I don't see Sansa and Arya.
Jaime: I don't have them.
Blackfish: Pity. Do you wish to resume your captivity? [Jaime shakes his head "no."] Then why are you here?
Jaime: You know why I'm here. This castle belongs to House Frey. You're trespassing. In the name of King Tommen, I order you to surrender, or...
Blackfish: Or you'll kill Edmure. My nephew's marked for death no matter what. Hang him and be done with it.
Jaime: It won't stop with Edmure. You'll force me to storm the castle. Hundreds will die.
Blackfish: Hundreds of mine. Thousands of yours. If you can breach the walls.
Jaime: We'll breach them, and kill every last one of you. But if you surrender, I'll spare the lives of your men, on my honor.
Blackfish: Your "honor." Bargaining with oath-breakers is like building on quicksand.
Jaime: The war is over, Ser. Why sacrifice living men to a lost cause?
Blackfish: As long as I'm standing, the war is not over. This is my home. I was born in this castle, and I'm ready to die in it. So you can either attack, or try to starve us out. We have enough provisions for two years. Do you have two years, Kingslayer?
Jaime: You clearly have no intention of saving your men's lives. Why did you come treat with me?
Blackfish: Sieges are dull, and I wanted to see you in person, get the measure of you.
Jaime: Well now you have.
Blackfish: Aye, now I have. I'm disappointed.
Brother Ray: Violence is a disease. You don't cure a disease by spreading it to more people.
Answer: As Hand of the King, Tywin is the second most authoritative person in Westeros behind only the king. The Hand's duties include sitting on The Iron Throne and dispensing order, justice and judgment, similar to what Ned Stark did in the Season 1 episode "A Golden Crown" while then-king Robert Baratheon was out hunting. It's also worth pointing out that Tywin's enormous wealth makes him the de facto most powerful person in Westeros, which he demonstrates in the Season 3 episode "Mhysa" when he sends King Joffrey to bed without his supper and remarks to Tyrion "You're a fool if you believe he's the most powerful man in Westeros. Do you really think the crown gives you power?"
Phaneron ★