Cherub and Seraph. Cherubim and seraphim (pl. of cherub and seraph) are at the very summit of the Celestial Hierarchy. They encircle the throne of the Godhead and protect the Ark of the Covenant with their wings. Isaiah (6:1-2) says: “I also saw the Lord sitting upon a throne, high and lifted up… Above it stood the Seraphim: each one had six wings.” The prophet Ezekiel (1:5-10) describes Cherubim: “They had the likeliness of men. And every one had four faces and every one had four wings… they four had the face of a man, and the face of a lion on the right side; and they four had the face of an ox on the left side; they four also had the face of an eagle”. These cherubim have men’s hands, feet like calves’ and eyes on their wings. Next to them, the prophet sees two coaxial wheels, also with eyes on wings.
See: Mikhail Vrubel: Six-winged Seraph (Azrael - the Angel of Death.)
Victor Vasnetsov. Seraphim. Seraphim.