Ezekiel 1:22-25

Spread out above them was a surface like the sky, glittering like crystal. Beneath this surface the wings of each living being stretched out to touch the others’ wings, and each had two wings covering its body. As they flew, their wings sounded to me like waves crashing against the shore or like the voice of the Almighty or like the shouting of a mighty army. When they stopped, they let down their wings. As they stood with wings lowered, a voice spoke from beyond the crystal surface above them.