Now it came to pass in the thirtieth year, in the fourth month, on the fifth day of the month, as I was among the captives by the River Chebar, that the heavens were opened and I saw visions of God.
References for Ezekiel 1:1
On the fifth day of the month, which was in the fifth year of King Jehoiachin's captivity,
the word of the Lord came expressly to Ezekiel the priest, the son of Buzi, in the land of the Chaldeans by the River Chebar; and the hand of the Lord was upon him there.
References for Ezekiel 1:3
Then I looked, and behold, a whirlwind was coming out of the north, a great cloud with raging fire engulfing itself; and brightness was all around it and radiating out of its midst like the color of amber, out of the midst of the fire.
Also from within it came the likeness of four living creatures. And this was their appearance: they had the likeness of a man.
Each one had four faces, and each one had four wings.
Their legs were straight, and the soles of their feet were like the soles of calves' feet. They sparkled like the color of burnished bronze.