This article argues that the emergence of the era of terrorism, fuelled in part by a form of Wahhabist Islam, impels a religious education imperative of improving understanding about Islam, both in terms of the historical roots with Judaism and Christianity, as well as ongoing conflict between the three traditions. On this basis, this article proposes content for religious education that challenges Westerners, especially of Jewish or Christian heritage, to come to an enhanced understanding about their sibling relationship with Islam, but also considers growing counter-propositions that this same Western world is the mortal enemy of Islam. In the case of both the positive and negative interpretations of the relationship between Islam and its sibling religions, the educational challenge is to enhance understanding of the self through increasing knowledge of the other.