When mercy and justice prevail, they work together to produce forgiveness. Without mercy, cruelty destroys the balance and vengeance follows. Because vengeance is not justice but reprisal, it destroys the vengeful as well as his victim.
In the world of Generation injury cannot be avoided. If, however, every injury is named a sin for which a punishment is required, there is soon an escalation to violence and vengeance. Opportunities are sought to strike out and brotherhood is destroyed. Blake uses the term 'impute sin' which implies that an infraction may be harmless until it is named a sin and becomes toxic. Blake introduced the concept of 'state' through which an individual passes in order to avoid imputing sin and to allow for the annihilation of error.
Man however can fall into the state of Ulro as described in Blake's Four Zoas: The Design of a Dream by Brian Wilkie and Mary Lynn Johnson:
"Ulro will be Blake's lowest state of existence, a world of pure unreality where all things are reduced to their lowest common denominator of spiritless physical matter. Brooding with nurselike solicitude over the ultimate home of the spectrous, the Daughters of Beulah condemn the corrupted sexuality of Tharmas and Enion, exposing the Spectre, or shadow personality in every man, for what it is in relation to full humanity, 'insane & most / Deformed.' (Page 28)
But the fall of man is arrested at the Ulro-point; the limits of time, space, matter, and the human body are set. The species and most human beings will survive - just barely - through Tharmas, the vestigial voice of instinct that signals the absurdity of all this unhappiness and waste, through Los, the power that makes possible even in the fallen state moments of ecstatic vision, and through that mysterious providence or hope that Blake calls Jesus, the Council of God.' (Page 83)
The will to survive, the vision of an alternative, and the Divine Providence enable man to abandon vengeance in exchange for life.
Book of Ahania, Plate 5, (E 90) "14: But now alone over rocks, mountains Cast out from thy lovely bosom: Cruel jealousy! selfish fear! Self-destroying: how can delight, Renew in these chains of darkness Where bones of beasts are strown On the bleak and snowy mountains Where bones from the birth are buried Before they see the light."
Milton, Plate 9, (E 103) "For Satan flaming with Rintrahs fury hidden beneath his own mildness Accus'd Palamabron before the Assembly of ingratitude! of malice: He created Seven deadly Sins drawing out his infernal scroll, Of Moral laws and cruel punishments upon the clouds of Jehovah To pervert the Divine voice in its entrance to the earth With thunder of war & trumpets sound, with armies of disease Punisbments & deaths musterd & number'd; Saying I am God alone There is no other! let all obey my principles of moral individuality I have brought them from the uppermost innermost recesses Of my Eternal Mind, transgressors I will rend off for ever, As now I rend this accursed Family from my covering." Jerusalem, Plate 25, (E 170) "And there was heard a great lamenting in Beulah: all the Regions Of Beulah were moved as the tender bowels are moved: & they said: Why did you take Vengeance O ye Sons of the mighty Albion? Planting these Oaken Groves: Erecting these Dragon Temples Injury the Lord heals but Vengeance cannot be healed: As the Sons of Albion have done to Luvah: so they have in him Done to the Divine Lord & Saviour, who suffers with those that suffer: For not one sparrow can suffer, & the whole Universe not suffer also, In all its Regions, & its Father & Saviour not pity and weep. But Vengeance is the destroyer of Grace & Repentance in the bosom Of the Injurer: in which the Divine Lamb is cruelly slain: Descend O Lamb of God & take away the imputation of Sin By the Creation of States & the deliverance of Individuals Evermore Amen Thus wept they in Beulah over the Four Regions of Albion But many doubted & despaird & imputed Sin & Righteousness To Individuals & not to States, and these Slept in Ulro." .