Something inside him hurts. He shuts it down out of a vague sense that letting this thing hurt will lead to other hurtings.
He doesn't know if 'Yes, Chosen' is an allowable thing to say here. If this is real, silence would be allowed; if it's fake... what does he say how to get out of hurting if it's fake...
"I owe you obedience, sir. You owe me nothing."