One of important issue that threatens Muslim unity is bid'ah issue. Several parties that dispute each other are Ahlussunnah,Mu'tazilah, Khawarij, and Murji'ah, between NU and Muhammadiyah, between Salafi, Wahabi, Ahmadiyah and others sects. On several ritualor social activity, they claim that their activity is the only true one and accord with Islamic teaching. Even, in Pakistan, Iraq, and Iran, bid'ah issuehave ignited bloody civil war between Muslim. There two position about bid'ah; first, ulama that posit all bid'ah are deviate. Second position, positthat bid'ah not generally astray; there astray and blamable (madzmumah), and also praised bid'ah (mahmudah). From different definition, theyalso have different method to understand proposition (dalil), and almost certainly they'll never be united. So, what have to done is givingcomprehensive understanding to ummat from extremist Muslim that deliberately astray and alters Muslim true and genuine understanding.