HARVEST & VINTAGE

Revelations 14
[15] And another angel came out of the temple, crying with a loud voice to him that sat on the cloud, Thrust in thy sickle, and reap: for the time is come for thee to reap; for the harvest of the earth is ripe.
[16] And he that sat on the cloud thrust in his sickle on the earth; and the earth was reaped.
[17] And another angel came out of the temple which is in heaven, he also having a sharp sickle.
[18] And another angel came out from the altar, which had power over fire; and cried with a loud cry to him that had the sharp sickle, saying, Thrust in thy sharp sickle, and gather the clusters of the vine of the earth; for her grapes are fully ripe.
[19] And the angel thrust in his sickle into the earth, and gathered the vine of the earth, and cast it into the great winepress of the wrath of God.
[20] And the winepress was trodden without the city, and blood came out of the winepress, even unto the horse bridles, by the space of a thousand and six hundred furlongs.

S. Foster Damon, William Blake: Philosophy and Symbols, in commenting on the final scenes in the Four Zoas, says (Page 164):

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AND GOD BLESSED THE SEVENTH DAY 
AND SANCTIFIED IT

"In six days heaven and earth had been created, according to Genesis, and on the seventh day the Lord rested. In six days, therefore, that work is to be reversed, before the Sabbath of the Millennium can arise. These six days are spent in a final Harvest and Vintage of the world, to make the Bread and Wine of Eternity. Urizen threshes the corn which Urthona bakes into the Bread of Philosophy, while Luvah presses the grapes into the Wine of Ecstacy; and all the chaff and refuse is cast into Non-Entity. This lovely festival in the spiritual world is the reality of what on earth seems to be the final catastrophes of the Apocalypse. During this time Orc burns himself out: Ahania and Enion rise to their former Glory; Luvah and Vala regain their original State of Innocence; while Los takes on his original form, Urthona. The terrific vision ends in a splendid peace:

[Four Zoas, PAGE 139, Night the Ninth, (E 406)]:
"How is it we have walkd thro fires & yet are not consumd
How is it that all things are changd even as in ancient times

The Sun arises from his dewy bed & the fresh airs
Play in his smiling beams giving the seeds of life to grow
And the fresh Earth beams forth ten thousand thousand springs of
life
Urthona is arisen in his strength no longer now
Divided from Enitharmon no longer the Spectre Los
Where is the Spectre of Prophecy where the delusive Phantom
Departed & Urthona rises from the ruinous walls
In all his ancient strength to form the golden armour of science
For intellectual War The war of swords departed now
The dark Religions are departed & sweet Science reigns

End of The Dream"

The image of the harvest and vintage appears in Milton as well:

Milton, PLATE 25 [27] (E 121)
"The Wine-press on the Rhine groans loud, but all its central beams
Act more terrific in the central Cities of the Nations
Where Human Thought is crushd beneath the iron hand of Power.
There Los puts all into the Press, the Opressor & the Opressed
Together, ripe for the Harvest & Vintage & ready for the Loom.

They sang at the Vintage. This is the Last Vintage! & Seed
Shall no more be sown upon Earth, till all the Vintage is over
And all gatherd in, till the Plow has passd over the Nations
And the Harrow & heavy thundering Roller upon the mountains

And loud the Souls howl round the Porches of Golgonooza

Crying O God deliver us to the Heavens or to the Earths,
That we may preach righteousness & punish the sinner with death
But Los refused, till all the Vintage of Earth was gatherd in.

And Los stood & cried to the Labourers of the Vintage in voice of
awe.

Fellow Labourers! The Great Vintage & Harvest is now upon Earth
The whole extent of the Globe is explored: Every scatterd Atom
Of Human Intellect now is flocking to the sound of the Trumpet
All the Wisdom which was hidden in caves & dens, from ancient
Time; is now sought out from Animal & Vegetable & Mineral

The Awakener is come. outstretchd over Europe! the Vision of God
is fulfilled
The Ancient Man upon the Rock of Albion Awakes,
He listens to the sounds of War astonishd & ashamed;"

Milton, PLATE 27 [29] (E 124)
"This Wine-press is call'd War on Earth, it is the Printing-Press
Of Los; and here he lays his words in order above the mortal
brain
As cogs are formd in a wheel to turn the cogs of the adverse
wheel."

Milton, PLATE 43 [50], (E 144)
"To go forth to the Great Harvest & Vintage of the Nations

Finis"

As Damon says, Blake wrote on multiple levels simultaneously. On the historical level the harvest and vintage appeared as the battles and wars which were taking place in his own times - the Napoleonic Wars ("Wine-press on the Rhine groans loud".) In Blake's personal experience the activities of his publishing work were his participation in the 'Great Harvest & Vintage' ("the Printing-Press Of Los; and here he lays his words in order above the mortal brain"). At the spiritual level they were the rewinding of the 'golden string' which had begun to be unwound with the material creation which Blake pictured in the Book of Urizen ("Every scatterd Atom Of Human Intellect now is flocking to the sound of the Trumpet").

Genesis 1
[5] And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
[8] And God called the firmament Heaven. And the evening and the morning were the second day.
[12] And the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.
[13] And the evening and the morning were the third day.
[17] And God set them in the firmament of the heaven to give light upon the earth,
[18] And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.
[19] And the evening and the morning were the fourth day.
[22] And God blessed them, saying, Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth.
[23] And the evening and the morning were the fifth day.
[27] So God created man in his own image, in the image of God created he him; male and female created he them
[31] And God saw every thing that he had made, and, behold, it was very good. And the evening and the morning were the sixth day.