On a proof print for the frontispiece of Jerusalem, there is text which does not appear on other known copies. The reason Blake deleted the text before making further prints is not known. Erdman includes the deleted text in the Complete Poetry and Prose of William Blake:
Jerusalem, Plate 1, (E 144) [Above the archway:] "There is a Void, outside of Existence, which if enterd into Englobes itself & becomes a Womb, such was Albions Couch A pleasant Shadow of Repose calld Albions lovely Land His Sublime & Pathos become Two Rocks fixd in the Earth His Reason his Spectrous Power, covers them above Jerusalem his Emanation is a Stone laying beneath O [Albion behold Pitying] behold the Vision of Albion [On right side of archway:] "Half Friendship is the bitterest Enmity said Los As he enterd the Door of Death for Albions sake Inspired The long sufferings of God are not for ever there is a Judgment [On left side, in reversed writing:] "Every Thing has its Vermin O Spectre of the Sleeping Dead!"
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From Fearful Symmetry by Northrop Frye:
"But as Milton and Jerusalem constitute a single epic, it is unlikely that any long interval separates the end of Milton from the beginning of Jerusalem. The same symbolism runs through both poems, the same methods ... Milton describes the attainment by the poet of the vision that Jerusalem expounds for all humanity." (Page 356)
Part of the text on Jerusalem's frontispiece is included in Milton as a question asked by Ololon:
Milton, Plate 41 , (E 143) "Then trembled the Virgin Ololon & replyd in clouds of despair Is this our Femin[in]e Portion the Six-fold Miltonic Female Terribly this Portion trembles before thee O awful Man Altho' our Human Power can sustain the severe contentions Of Friendship, our Sexual cannot: but flies into the Ulro. Hence arose all our terrors in Eternity! & now remembrance Returns upon us! are we Contraries O Milton, Thou & I O Immortal! how were we led to War the Wars of Death Is this the Void Outside of Existence, which if enterd into Plate 42  Becomes a Womb? & is this the Death Couch of Albion Thou goest to Eternal Death & all must go with thee So saying, the Virgin divided Six-fold & with a shriek Dolorous that ran thro all Creation a Double Six-fold Wonder! Away from Ololon she divided & fled into the depths Of Miltons Shadow as a Dove upon the stormy Sea."
Ololon represents a potential for redemption provided by Eternity. Several of her forms are presented by Blake. When Milton goes to annihilation Ololon is transformed. As stated by Damon: "The Starry Eight become Jesus; Ololon's clouds are his wedding garment; and Jesus becomes one with mankind (42:19). The mystical union has been achieved, and Blake falls fainting on his garden path."
The text on the frontispiece of Jerusalem served as a link to Milton and as a preview to the tensions and themes which would be developed in Jerusalem. Apparently Blake decided to let the image speak for itself and deleted the text. But the single copy was not destroyed and it comes to us through many hands to be a puzzle for us to solve.