An individual’s identity is also defined based on the religious system to which he or she belongs. But who, among the young generation, truly knows, in the sense of the imaginaire, the monotheistic religious truth which Islamism and Christianity share ? It is important to see how each monotheism is built as a system of coherence. But coherence, identified with truth, excludes that of the Other. In this perspective, is religion a factor of union or division?