It is well known that the People of the Book are closer to the Muslims than the Magians, Sabians, and polytheists. Thus, the first religious innovations to emerge bore some resemblance to Judaism and Christianity. Whenever the light of prophethood shines forth, religious innovations die out. Prophethood was most manifest in the earliest period, so only comparatively less serious innovations appeared, such as the innovation of the Khārijites, which emerged toward the end of the era of the Rightly Guided Caliphs