Here "Judah" refers to the king of Judah. Alternate translation: "the rule of the king of Judah" or "the authority of the king of Judah" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Libnah rebelled against the king of Judah just as Edom had. Alternate translation: "During that same time, Libnah also rebelled against the king of Judah" (See: [[rc://en/ta/man/translate/figs-explicit]])
This is another city that was originally part of Judah. Here "Libnah" refers to the people who live there. Alternate translation: "the people of Libnah" (See: [[rc://en/ta/man/translate/translate-names]] and [[rc://en/ta/man/translate/figs-metonymy]])