"Let us agree to give up love"
What would an ordinary layman make of that verse? "Well he's just crazy!"
You might say he started with a low view of love; but don't we all? 'the sailor goes to the brothel for love' (one of the lower views of the word). Blake didn't condemn that; he condemned the love of filthy lucre by the uppers that led to merciless exploitation and impoverishment of the poor to enrich themselves (btw that still goes on).
He condemned the sanctimonious laws of sex that often led to fallen women being forced to sell their bodies in order to eat:
"Every harlot was a virgin once."
"Truly My Satan thou art but a Dunce
And dost not know the Garment from the Man
(King Jim's Bible (and most other English translations slanted Isaiah's innocent word
to 'invent' the "Virgin Birth" (so to speak)).
It's important to realize that these formative metaphors that made up Blake's poetic vocabulary changed their meanings with time:
Start with "The Torments of Love and Jealousy" in the subtitle of The Four Zoas and end with Los embracing Urizen: He "found his Enemy Urizen now In his hands. he wonderd that he felt love & not hate His whole soul loved him he beheld him an infant" (4z, night 7a; E371) (Try that on in your attempts to forgive your favorite enemy: behold him an infant. It's sheerly impossible for most of us to hate an infant!)
As Blake matured and his spiritual understanding developed, the metaphors (at first low) were ennobled. The end of this process for all of us is to go from hate to love. That was Jesus' purpose, and when Blake truly met him, the darkness turned to mid-day.
Annotations to Lavater, (E 599)
"Whoso dwelleth in love dwelleth in God &
God in him. & such an one cannot judge of any but in love."