When Jeremiah was teaching repentance in Jerusalem, Ezekiel worked with the people that were in Babylonian captivity. Ezekiel was taken to Babylon in about 597 B.C. when King Jehoiachin was overthrown by Nebuchadnezzar and carried into captivity. It was there that Ezekiel received his call to be a prophet to the Jews.
While there, Ezekiel tried to help his people understand that their captivity was a result of their wickedness. His message was a warning of judgment and of mercy that left no doubt of the Lord's anger nor of his desire for the people's repentance. We find in the book of Ezekiel that God is in control and desires that all of His children come unto Him.
There are six key messages in the book of Ezekiel in the Old Testament: 1) Ezekiel's call and commission to be a prophet; 2) Prophecies condemning the sins of the people in the land of Israel, especially in Jerusalem, culminating in the fall and capture of Jerusalem by the Babylonians; 3) Prophecies calling the Jews in Babylon to repentance; 4) Prophecies concerning the destruction of the countries surrounding Israel who were their enemies – mainly Ammon, Moab, Edom, Philistia, Tyre, Sidon, and Egypt; 5) Prophecies about the gathering of Israel and other events in preparation for the Second Coming of the Savior, and; 6) A description of Ezekiel's vision of a temple being built in Jerusalem at some future time and the manner of worship within.
"Ezekiel was a man of many visions and spoke much about the future restoration of Israel and the glory of the millennial reign of the Lord. The authenticity of his writings are specifically confirmed by latter-day revelation, as in Doctrine and Covenants 29:21."1
1 "Holy Bible", Bible Dictionary – Ezekiel