Numbers 10-13 in this chapter about the instruments for good works:
10. To deny oneself in order to follow Christ.
11. To chastise the body.
12. Not to become attached to pleasures.
13. To love fasting.
provide a fascinating perspective from which to view number 9:
9. And not to do to another what one would not have done to oneself.
Our culture generally conceives of the Golden Rule with regard to simple pleasure or pain: "I don't want to feel pain, so I won't cause it in others," but our Father Benedict prescribes a treatment of oneself that is difficult and unpleasant in the service of transformation.
So perhaps I should ask myself the question, "which 'me' does not want to be treated in such and such a way," when considering my actions towards others. Is it the me that wants to be transformed and is willing to suffer difficulty and unpleasantness in order to change? Or is it the me that simply wants to feel pleasure and not pain?
Jesus practiced the Deeper Golden Rule when he did not hesitate to rebuke Peter in the moments after Peter's confession of Jesus as the Christ. Peter had let pride arise in the moments after Jesus had praised him for speaking God's words, and when he spoke again, this time to contradict the call of God upon the Christ, Jesus calls the place from which Peter spoke "Satan." The Golden Rule can seem harsh at times in the service of transformation, but it is always good.