Still confused about Vader Sidious Luke confrontation

Ok, Vader was planning on Luke and him overthrowing the emporer and the emporer wanted Luke to replace Vader, right? So then why doesn Vader block Luke's strike at the emporer?

 

He must obey his master.

 

Emperor Palpatine wanted luke to "strike him down." He had been goading Luke into doing that when he revealed to Luke the traps he had laid for the Leia and Han on Endor and the Rebel fleet attacking the Death Star.

Now that we've seen what Palpatine can do in the PT, it's likely he would've used the Force to throw Luke back or strike him with Sith lightning when Luke tried to kill him with his lightsaber. That would've completed Luke's journey to the Dark Side.

Darth Vader wants Palpatine dead, but he needs Luke's help to do it. Vader also wants his son to accept the Dark Side, but not for Palpatine's motives. Vader wasn't protecting Palpatine when he blocked Luke's lightsaber, he was protecting Luke from Palpatine.

 

Did Palpatine know that he was trying to save Luke?

 

Vader wanted Palpatine dead, but he had to obey Palpatine. He was torn completely, I think.

 

Did Palpatine know that he was trying to save Luke?

It's likely. Palpatine knows that he can't trust Vader anymore and he's seen how different Vader has acted since ESB.

 

Vader at this point is one messed up guy: he wants to be numero uno, he has to obey his master, and he has this thing going on with Luke...

So messed up that someone else, yep, does the Force-choking in ROTJ...

 

Anakin...Vader...hes been confused since day one.. The whole going to the darkside thing was all out of love for Padme ( if you read the book it goes more into his thoughts)When Annies main squeeze bit the big one that pushed his fragile little behind over the edge..pushing him into the darkside. But when the bad man in black finds out hes a pop..he gets all confused again.

 

It all boils down to intent. Vader wasn't going to let Luke kill the Emperor. But with Palpatine talking trash and making Luke angry, Luke reached for his weapon with the INTENT to kill the Emperor. Although Darth Vader had silent motives of wanting to do away with the Emperor, he played along with the Emperor's game and did things his way. The Emperor told him that they could only turn Luke to the dark side as a team, not individually.

 

According to the book version of ROTJ, anyway, Vader was doubtful that Luke would go to the dark side if he killed the Emperor right then. Vader wanted to give himself more time to convert Luke, so he blocked Luke's strike.