JAKARTA, Indonesia—Opposition leader Prabowo Subianto returned to the political scene with a message for the man who defeated him in last year’s election: the opposition parties in parliament respect and support President Joko Widodo even more than the parties in his own coalition.

“For the past few months, it is the Red and White Coalition that has been most supportive” to the president in Parliament, said former Gen. Subianto, referring the opposition coalition he leads that controls the majority of seats in the 560-seat...