The Book of Ezekiel narrates the story of Ezekiel, who was a priest in Israel after the Babylonian capture of the land. At about the time when he would have been appointed as a prophet, he has a vision of God's manifestation. He is instructed to warn the Israelites to follow their covenant with God. The Israelites by this time had begun to worship other gods and idols. This had spawned social ills of all kinds. So Ezekiel begins to spread the word that unless the Israelites repent and obey God, another attack would follow on Israel and the temple would be destroyed. Ezekiel is also told by God that the Israelites will not listen to him because their hearts have become hard and unruly. Sure enough, the prophecy is fulfilled when Israel is attacked a second time and the temple is destroyed. Ezekiel also begins to have visions of God's mercy that if the Israelites soften their hearts and obey God, He will love them back and restore their glory. And that is the essence of the Book of Ezekiel.
