fiery (serpent), seraph, seraphim
“Beasts, the Four” From Dictionary of Biblical Words:
These are not beasts, but living creatures, combining the six wings and the cry of “Holy, holy, holy” of the seraphim in Isa. 6 with the four appearances and the eyes of the cherubim of Ezek. 1 The four faces embrace all creation—man, cattle, beasts of the field, and fowls of the air. They are the executive instruments of the throne of God, combining intelligence, firmness, power and rapidity. They are an instance of what is often found in Scripture: the combination of two things after the cross that are separate before.
“Seraphim” From Dictionary of Biblical Words:
It differs from the cherubim in having six wings instead of four (Isa. 6:2), and in being instruments of mercy instead of judgment, like the cherubim. The four beasts in the Revelation combine the two. See CHERUBIM, FOUR BEASTS.
Boyd’s Bible Dictionary:
(burning). An order of celestial bearings, pictured in Isaiah’s vision as around the throne of God (Isa. 6:2-7).
Concise Bible Dictionary:
Symbolical celestial beings seen by Isaiah standing above the Lord on His throne (Adonai, but many MSS read Jehovah). Each had three sets of wings: with one pair he covered his face, in token of reverence; with another he covered his feet, in token of humility; and with the third he flew to accomplish his mission.
Gesenius and Fürst give to the word saraph the meanings “to burn,” and “to be exalted.” They trace the seraphim to the latter signification, as “exalted ones.” The word occurs only in Numbers 21:6; Deuteronomy 8:15, translated “fiery;” and in Numbers 21:8; Isaiah 14:29 and Isaiah 30:6, translated “fiery serpent.” In Isaiah 6:2-7 (the plural) the seraphim are exalted beings, but the only actions recorded there are that one brought a live coal from off the altar and laid it upon the prophet’s mouth, and said, “Thine iniquity is taken away, and thy sin purged.” They cried to one another, “Holy, holy, holy is Jehovah of hosts; the whole earth is full of his glory.”
The distinction between seraphim and cherubim may be that, while the former bear witness to God’s holiness (that is, to His nature), in the latter are exhibited the principles of His righteous government on the earth. The “living creatures” of Revelation 4 combine the characteristics of both cherubim and seraphim.
Strong’s Dictionary of Hebrew Words:
Meaning:
from 8313; burning, i.e. (figuratively) poisonous (serpent); specifically, a saraph or symbolical creature (from their copper color)
KJV Usage:
fiery (serpent), seraph