The Jewish faith and by implication the whole Abrahamic tradition is based on a few significant events, one of which is the magnificent theophany of Sinai. Sinai, which has not been positively identified is thought to be one of a cluster of peaks reaching 9000 feet in the Sinai desert. The Hebrews, under Moses and Aaron, had fled from slavery in Egypt and were making for the mountain, which for them seems to have been a holy place, aided, by strange coincidence, in all probability, by the smoke and fires of yet another mountain, the volcano Thera, the wreckage of which is the present day island cluster of Santorini.
It was at Mount Sinai that the theophany occurred that shaped the history of the Jews, the faith from which not only modern Judaism, but both Christianity and Islam arose. It was at Sinai that Moses ascended the mountain to receive the stone tablets were inscribed with the main tenets of the law, the keeping of which constituted the Hebrews' side of the covenant with God. The covenant that God would be the Hebrews' [lsrael's] God in return for keeping God's law has been fundamental to Israel's identity and religious thought in that time. The concept of the New Covenant is fundamental to the story of Jesus and his mission. The Jewish Passover and the Christian Eucharist are celebrations of the original and new covenants respectively.
No account of worship on hills and mountains in the Holy Land could fail to mention high places, which were hill top shrines used for sacrifices and feasts. These ancient sites were local places of worship, but they fell into disfavour when King David centralised sacrifice in Jerusalem and dwindled until the exile, when rabbinic Judaism which worshipped in synagogues replaced the remaining few of them.
The New Testament continues the mountain theme, as it begins with Jesus' sermon on the mount. The parallel with the giving of the old covenant and law on Mount Sinai and Jesus' sermon is clear. Just as God sends the old law symbolized by the commandments on Sinai, so Jesus, God's Son and messenger, presents the new law symbolized by the eight beatitudes on the mountain. A great religious change is signaled. It seems likely that Matthew includes teaching material in the Sermon that was uttered on other occasions if it fits into the sermon, and we cannot prove that there was a real sermon on the mount. But in a hilly place such as Palestine hills are hard to avoid. So it is reasonable to judge that Jesus gave a sermon from a hillside.
The parallel between the Sinai theophany and the sermon on the mount is that God speaks from the mountain to give his law. The implication is that Matthew's gospel is presenting Jesus as God's representative among humankind, his son. The differences are that at Sinai was that there was a thunderous storm, signifying God's power, whereas Jesus speaks in a normal preaching style without spectacular demonstrations. This is in line with the tradition of Elijah in the cave, but more about that tradition later.
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