This is a request. To carry out what one has said is an idiom meaning to do what one has said. Alternate translation: "please do what you have promised" (See: [[rc://en/ta/man/jit/figs-idiom]])
The throne is a metonym for the activity of the one who sits on the throne. Alternate translation: "to rule over Israel" (See: [[rc://en/ta/man/jit/figs-metonymy]])
The way a person behaves is spoken of as if that person were walking on a path. Alternate translation: "to obey my law, as you have obeyed me" or "to be faithful to my law as you have been faithful to me" (See: [[rc://en/ta/man/jit/figs-metaphor]])