“one will sit on it in faithfulness.” The “one” is the Messiah, Jesus Christ. In the Millennial Kingdom, when Jesus Christ rules the earth from Jerusalem, he will sit on a throne and administer justice to the world. [For more on the Millennial Kingdom in Isaiah, see commentary on Isa. 2:2. For more on the Millennial Kingdom, see Appendix 3, “Christ’s Future Kingdom on Earth”].

“what is right.” The Hebrew is “righteousness,” which in this context is “what is right,” or as some English versions have, “justice.” [For more on “righteousness” referring to what is right or to “justice,” see commentary on Matthew 5:6].