Cherub/Cherubim - Exact origin unknown, but perhaps borrowed from Assyrian for either "to bless" or "to pray." Another possibility is the Hebrew word "near" (qareb), which is used to indicate coming near to God for worship or sacrifice. The symbolism of Ezekiel suggests powerful and wise creatures. The Living Creatures seem to be the same beings.

Genesis 3:1-24
    Now the serpent was the most cunning of all the animals that the LORD God had made. The serpent asked the woman, "Did God really tell you not to eat from any of the trees in the garden?" [2] The woman answered the serpent: "We may eat of the fruit of the trees in the garden; [3] it is only about the fruit of the tree in the middle of the garden that God said, 'You shall not eat it or even touch it, lest you die.' " [4] But the serpent said to the woman: "You certainly will not die! [5] No, God knows well that the moment you eat of it your eyes will be opened and you will be like gods who know what is good and what is bad." [6] The woman saw that the tree was good for food, pleasing to the eyes, and desirable for gaining wisdom. So she took some of its fruit and ate it; and she also gave some to her husband, who was with her, and he ate it. [7] Then the eyes of both of them were opened, and they realized that they were naked; so they sewed fig leaves together and made loincloths for themselves.
    [8] When they heard the sound of the LORD God moving about in the garden at the breezy time of the day, the man and his wife hid themselves from the LORD God among the trees of the garden. [9] The LORD God then called to the man and asked him, "Where are you?" [10] He answered, "I heard you in the garden; but I was afraid, because I was naked, so I hid myself." [11] Then he asked, "Who told you that you were naked? You have eaten, then, from the tree of which I had forbidden you to eat!" [12] The man replied, "The woman whom you put here with me--she gave me fruit from the tree, so I ate it." [13] The LORD God then asked the woman, "Why did you do such a thing?" The woman answered, "The serpent tricked me into it, so I ate it."
    [14] Then the LORD God said to the serpent:
    "Because you have done this, you shall be banned
        from all the animals
        and from all the wild creatures;
    On your belly shall you crawl,
        and dirt shall you eat
        all the days of your life.
    [15] I will put enmity between you and the woman,
        and between your offspring and hers;
    He will strike at your head,
        while you strike at his heel."
[16] To the woman he said:
    "I will intensify the pangs of your childbearing;
        in pain shall you bring forth children.
    Yet your urge shall be for your husband,
        and he shall be your master."
[17] To the man he said: "Because you listened to your wife and ate from the tree of which I had forbidden you to eat,
    "Cursed be the ground because of you!
    In toil shall you eat its yield
    all the days of your life.
    [18] Thorns and thistles shall it bring forth to you,
        as you eat of the plants of the field.
    [19] By the sweat of your face
        shall you get bread to eat,
    Until you return to the ground,
        from which you were taken;
    For you are dirt,
        and to dirt you shall return."
   [20] The man called his wife Eve, because she became the mother of all the living.
    [21] For the man and his wife the LORD God made leather garments, with which he clothed them. [22] Then the LORD God said: "See! The man has become like one of us, knowing what is good and what is bad! Therefore, he must not be allowed to put out his hand to take fruit from the tree of life also, and thus eat of it and live forever." [23] The LORD God therefore banished him from the garden of Eden, to till the ground from which he had been taken. [24] When he expelled the man, he settled him east of the garden of Eden; and he stationed the cherubim and the fiery revolving sword, to guard the way to the tree of life.

Psalm 80 [Vulgate Ps. 79]
For the leader; according to "Lilies." Eduth. A psalm of Asaph.
    I
    [2] Shepherd of Israel, listen,
        guide of the flock of Joseph!
    From your throne upon the cherubim reveal yourself
       [3] to Ephraim, Benjamin, and Manasseh.
    Stir up your power, come to save us.
       [4] O LORD of hosts, restore us;
    Let your face shine upon us,
        that we may be saved. 
     II
    [5] LORD of hosts,
        how long will you burn with anger
        while your people pray?
    [6] You have fed them the bread of tears,
        made them drink tears in abundance.
    [7] You have left us to be fought over by our neighbors;
        our enemies deride us.
    [8] O LORD of hosts, restore us;
        let your face shine upon us,
        that we may be saved.
    III
    [9] You brought a vine out of Egypt;
        you drove away the nations and planted it.
    [10] You cleared the ground;
        it took root and filled the land.
    [11] The mountains were covered by its shadow,
        the cedars of God by its branches.
    [12] It sent out boughs as far as the sea,
        shoots as far as the river.
    [13] Why have you broken down the walls,
        so that all who pass by pluck its fruit?
    [14] The boar from the forest strips the vine;
        the beast of the field feeds upon it.
    [15] Turn again, LORD of hosts;
        look down from heaven and see;
    Attend to this vine,
    [16] the shoot your right hand has planted.
    [17] Those who would burn or cut it down--
        may they perish at your rebuke.
    [18] May your help be with the man at your right hand,
        with the one whom you once made strong.
    [19] Then we will not withdraw from you;
        revive us, and we will call on your name.
     [20] LORD of hosts, restore us;
        let your face shine upon us,
        that we may be saved.

Psalm 99 [Vulgate 98]
    I
    The LORD is king, the peoples tremble;
        God is enthroned on the cherubim, the earth quakes.
    [2] The LORD is great on Zion,
        exalted above all the peoples.
    [3] Let them praise your great and awesome name:
        Holy is God! 
    [4] II
    O mighty king, lover of justice,
        you alone have established fairness;
        you have created just rule in Jacob.
    [5] Exalt the LORD, our God;
        bow down before his footstool;
        holy is God! 
    [6] III
    Moses and Aaron were among his priests,
        Samuel among those who called on God's name;
        they called on the LORD, who answered them.
    [7] From the pillar of cloud God spoke to them;
        they kept the decrees, the law they received.
    [8] O LORD, our God, you answered them;
        you were a forgiving God,
        though you punished their offenses.
    [9] Exalt the LORD, our God;
        bow down before his holy mountain;
        holy is the LORD, our God.

Isaiah 37
    [1] When King Hezekiah heard this, he tore his garments, wrapped himself in sackcloth, and went into the temple of the LORD. [2] He sent Eliakim, the master of the palace, and Shebna the scribe, and the elders of the priests, wrapped in sackcloth, to tell the prophet Isaiah, son of Amoz: [3] "Thus says Hezekiah: 'This is a day of distress, of rebuke, and of disgrace. Children are at the point of birth, but there is no strength to bring them forth. [4] Perhaps the LORD, your God, will hear the words of the commander, whom his master, the king of Assyria, sent to taunt the living God, and will rebuke him for the words which the LORD, your God, has heard. Send up a prayer for the remnant that is here.' "
    [5] When the servants of King Hezekiah had come to Isaiah, [6] he said to them: "Tell this to your master: 'Thus says the LORD: Do not be frightened by the words you have heard, with which the servants of the king of Assyria have blasphemed me. [7] I am about to put in him such a spirit that, when he hears a certain report, he will return to his own land, and there I will cause him to fall by the sword.' "
    [8] When the commander returned to Lachish and heard that the king of Assyria had left there, he found him besieging Libnah. [9] The king of Assyria heard a report that Tirhakah, king of Ethiopia, had come out to fight against him. Again he sent envoys to Hezekiah with this message: "Thus shall you say to Hezekiah, king of Judah: [10] 'Do not let your God on whom you rely deceive you by saying that Jerusalem will not be handed over to the king of Assyria. [11] You yourself have heard what the kings of Assyria have done to all the countries: They doomed them! Will you, then, be saved? [12] Did the gods of the nations whom my fathers destroyed save them? Gozen, Haran, Rezeph, and the Edenites in Telassar? [13] Where is the king of Hamath, the king of Arpad, or a king of the cities of Sepharvaim, Hena or Ivvah?' "
   [14] Hezekiah took the letter from the hand of the messengers and read it; then he went up to the temple of the LORD, and spreading it out before him, [15] he prayed to the LORD: [16] "O LORD of hosts, God of Israel, enthroned upon the cherubim! You alone are God over all the kingdoms of the earth. You have made the heavens and the earth. [17] Incline your ear, O LORD, and listen! Open your eyes, O LORD and see! Hear all the words of the letter that Sennacherib sent to taunt the living God. [18] Truly, O LORD, the kings of Assyria have laid waste all the nations and their lands, [19] and cast their gods into the fire; they destroyed them because they were not gods but the work of human hands, wood and stone. [20] Therefore, O LORD, our God, save us from his hand, that all the kingdoms of the earth may know that you, O LORD, alone are God."
    [21] Then Isaiah, son of Amoz, sent this message to Hezekiah: Thus says the LORD, the God of Israel: In answer to your prayer for help against Sennacherib, king of Assyria, [22] this is the word the LORD has spoken concerning him:
    She despises you, laughs you to scorn,
        the virgin daughter Zion;
    Behind you she wags her head,
        daughter Jerusalem.
    [23] Whom have you insulted and blasphemed,
        against whom have you raised your voice
    And lifted up your eyes on high?
        Against the Holy One of Israel!
    [24] Through your servants you have insulted the Lord:
        You said, "With my many chariots
    I climbed the mountain heights,
        the recesses of Lebanon;
    I cut down its lofty cedars,
        its choice cypresses;
    I reached the remotest heights,
        its forest park.
    [25] I dug wells and drank water in foreign lands;
        I dried up with the soles of my feet
        all the rivers of Egypt.
    [26] Have you not heard?
        Long ago I prepared it,
    From days of old I planned it,
        now I have brought it to pass:
    That you should reduce fortified cities
        into heaps of ruins,
    [27] While their inhabitants, shorn of power,
        are dismayed and ashamed,
    Becoming like the plants of the field,
        like the green growth,
        like the scorched grass on the housetops.
    [28] I am aware whether you stand or sit;
        I know whether you come or go,
        and also your rage against me.
    [29] Because of your rage against me
        and your fury which has reached my ears,
    I will put my hook in your nose
        and my bit in your mouth,
        and make you return the way you came.
    [30] This shall be a sign for you:
        this year you shall eat the aftergrowth,
        next year, what grows of itself;
    But in the third year, sow and reap,
        plant vineyards and eat their fruit!
    [31] The remaining survivors of the house of Judah
        shall again strike root below
        and bear fruit above.
    [32] For out of Jerusalem shall come a remnant,
        and from Mount Zion, survivors.
        The zeal of the LORD of hosts shall do this.
    [33] Therefore, thus says the LORD concerning the king of Assyria: He shall not reach this city, nor shoot an arrow at it, nor come before it with a shield, nor cast up siegeworks against it. [34] He shall return by the same way he came, without entering the city, says the LORD. [35] I will shield and save this city for my own sake, and for the sake of my servant David.
    [36] The angel of the LORD went forth and struck down one hundred and eighty-five thousand in the Assyrian camp. Early the next morning, there they were, all the corpses of the dead. [37] So Sennacherib, the king of Assyria, broke camp and went back home to Nineveh.
    [38] When he was worshiping in the temple of his god Nisroch, his sons Adrammelech and Sharezer slew him with the sword and fled into the land of Ararat. His son Esarhaddon reigned in his stead.