Quoted from: Boland, B. J. 1971. The struggle of Islam in modern Indonesia. The Hague: Nijhoff. Pp. 145-146.“An influential Muslim told me that in Java (perhaps in Central Java) a fatwā of the Muhammadiyah chairman had been a great significance in the extermination of the “Gestapu/P.K.I.”, because in this fatwā it was stated that their destruction ought to be considered a religious duty. The informant was probably referring to the statement issued at an emergency meeting of the Muhammadijah held on November 9th- 11th, 1965, in Djakarta.
From this period, there are more statements known, made by Muslim leaders who declared this conflict to be a “Holy War”. This Muhammadijah statement, however, can be taken as an authoritative example.”
Under the heading Ibadah dan Djihad (Religious Duty and the Holy War), this statement explains that the action on September 30th, 1965, is to be regarded as an extension of the Madiun Communist rising of 1948. Officers such as Untung, Latif, Supardjo, Bambang Supeno and others are said to have been involved in the Madiun Affair. Therefore this time a decisive follow-up ought to be carried through in order to prevent a third Communist attempt at a coup in the future. The statement continues as follows:
“Therefore it was right for the Muhammadiyah, together with [the leaders of] its youth movement, during an emergency meeting in Djakarta, November 9th-11th, 1965, trusting in God (tawakkal), to make this pronouncement: THE EXTERMINATION OF THE GESTAPU/PKI AND THE NEKOLIM IS A RELIGIOUS DUTY. … This religious duty is not (only) recommended (sunnat) but obligatory (wadjib), even an individual obligation” (wadjib `ain…) … “And because this action and this struggle must be carried out by consolidating all our strength –mental, physical and material—therefore this action and this struggle are nothing less than a HOLY WAR (DJIHAD). This Holy War, according to religious law, is not (only) recommended, but obligatory, even an individual obligation…” Finally it is stated –in accordance with Islamic law—that when carrying out this djihad “destructive excesses, defamation, revenge, etc. must be prevented”.
It is not explicitly stated what interpretation the (modern) Muhammadijah at that moment gave to the term djihad. But the conclusion drawn by the average Muslim as well as his enemy can easily be guessed. It is, however, hard to assess to what extent this fatwā had a result similar to that which earlier “djihad resolution” had on events in Surabaja in November 1945.