The second use of Satan refers to the demons that serve Satan. Alternate translation: "If Satan works against his own demons" (See: [[rc://en/ta/man/jit/figs-metonymy]])
Jesus uses this question to show the Pharisees that what they were saying was illogical. Alternate translation: "His kingdom would not be able to stand!" or "His kingdom would not last!" (See: [[rc://en/ta/man/jit/figs-rquestion]])