According to ‘The ancient world’, burial evidence points to three main models of our earliest religious beliefs: the notion of the earth mother; veneration of the dead, and by extrapolation ancestor worship; and animism. Elements of these can also be found in the religions of the historic world. Many forms of religious worship were practised across the Greco–Roman world. While state religion provided a unifying expression of Roman identity across the Empire, syncretism was common. However, Christians did not want to join in. In the first few centuries of the Church, Christian theologians were particularly critical of three practices they saw as defining paganism: polytheism, sacrifice, and idol worship.