Cherubim

In Genesis 2:4 after Adam and Eve had sinned we read
3:24ff "So he drove out the man; and he placed at the east
of the garden of Eden Cherubim, and a flaming sword
which turned every way, to keep the way of the tree of life."

Blake commented on that in The Marriage of Heaven and Hell:
"the cherub with his flaming sword is hereby commanded to 

 leave his guard at the tree of life, and when he does, the
whole creation will be consumed, and appear infinite. and
holy whereas it now appears finite & corrupt. This will come to 

pass by an improvement of sensual enjoyment."

---

The Book of Ezekiel begins with an excoriation of The Prince of 

Troy who had treated the Hebrews  violently.

In Chapter 1 we read:
"[16] By the multitude of thy merchandise they have filled
the midst of thee with violence, and thou hast sinned:
therefore I will cast thee as profane out of the mountain of
God: and I will destroy thee, O covering cherub, from the
midst of the stones of fire."

And this from Blake's Book of Milton, Plate 10:

"And Satan not having the Science of Wrath, but only of Pity:
Rent them asunder, and wrath was left to wrath, & pity to pity.
He sunk down a dreadful Death, unlike the slumbers of Beulah
The Separation was terrible: the Dead was repos'd on his Couch
Beneath the Couch of Albion, on the seven mou[n]tains of Rome  
In the whole place of the Covering Cherub, Rome Babylon & Tyre.
His Spectre raging furious descended into its Space" 

(Erdman 103-04)

And from Blake's Book of Milton, Plate 23/25:

"Awake Albion awake!          
Lo Orc arises on the Atlantic. Lo his blood and fire
Glow on Americas shore: Albion turns upon his Couch
He listens to the sounds of War, astonishd and 
confounded:
He weeps into the Atlantic deep, yet still in dismal 
dreams Unwakend! 
and the Covering Cherub advances from the East:        
How long shall we lay dead in the Street of the 
great City
How long beneath the Covering Cherub give our 
Emanations;
Milton will utterly consume us & thee our beloved 
Father He hath enterd into the Covering Cherub, 
becoming one with Albions dread Sons,"

From that we surmise that the Covering Cherub is the 
sum total the war that keeps us all from the Garden.