Simply called Living creatures in Ezekiel's text from the Old Testament, they were four divine beings that accompanied the chariot of God. They were described as possessing the faces of a man, a lion, an ox, and an eagle that faced the four cardinal directions. Depending on the text they may have possessed four or six wings. Alongside side each of them was a wheel described as a "wheel within a wheel" and possessing "eyes all around." These normally are referred to as Ezekiel's wheels. The Book of Enoch would build upon this later.
In their description in Revelation 4:6–8 from the New Testament, the Living creatures are described as possessing "eyes before and behind" instead of being accompanied by an Ezekiel's wheel. This is the only time 'angels' are depicted as such in the New Testament, with their other appearances being the more humanized version typically seen in Christendom.