Isaiah 6:2

Above it … seraphims better, Seraphim were standing over Him, i.e. in the attitude of service. One standing in the presence of another who is seated is always said to be overhim, whatever their mutual relations may be: 1 Kings 22:19; Genesis 18:2; Genesis 18:8; Exodus 18:13, &c. The Seraphim (probably "fiery beings") are mentioned nowhere else in Scripture as angelic beings. Their function in this vision is purely symbolical. They are the attendants of Jehovah's court or the ministers of the invisible sanctuary; they reflect the glory of God, and by their presence and actions suggest new and fuller conceptions of His ineffable majesty. The basis of the symbol is obscure. The serpents with which the Israelites were plagued in the desert are called Seraphim (sing. Sârâph: Numbers 21:6-9; Deuteronomy 8:15), and some connexion between the two uses of the word is probable. An intermediate link would be supplied by the "flying Saraph" of ch. Isaiah 14:29; Isaiah 30:6, apparently an allusion to a widely diffused mythological notion; see Herodotus II. 75 on the winged serpents of Arabia. It is also worthy of notice that the brazen Saraph (Numbers 21:8) made by Moses must have been a conspicuous object in the temple at the time of Isaiah's call (2 Kings 18:4). On the other hand the analogy of the Cherubim has led to the theory that both are personifications of the phenomena of the thunder-storm, the Cherubim representing the dark cloud and the Seraphim the serpent-like lightning (see Cheyne, Comm., and art. -Cherubim" in Encyc. Brit.). Different elements, in fact, seem to be combined in the conception of the Saraph; but whether it had been already incorporated in the religion of Israel, or whether Isaiah was the first who lifted it into the sphere of pure spiritual ideas it is quite impossible to say. Isaiah's Seraphim are winged creatures, but certainly not serpentine in form, probably human, or at least partly human, like the Cherubim (Ezekiel 1:5-14).

with twain he covered his face The sense is well expressed by the Targum: "With two he covered his face that he might not see;and with two he covered his body that he might not be seen."