There's a polite way to do everything. Being polite doesn't mean the other guy won't like what you are saying or doing. But if you're boss doesn't like you repeating back your instructions, what's his complaint? That you're trying too hard to get his instructions right?

Personally, I love it when my guys repeat back my orders. It tells me they are invested in making sure they get the job done right. It's good communication. Likewise, if one of my seniors is giving me instructions or whatever, I repeat it back to make sure I understood correctly. With some of my people, I make them repeat back what I tell them to do.