Praised by poet Algernon Swinburne as the greatest of Blake's works and called by Geoffrey Keynes "the most exciting and readable of all Blake's books," The Marriage of Heaven and Hell is distinct from Blake's other illuminated texts by its mixture of form, consisting of a poetical "Argument" and six sections of prose dogma, with a final "Song of Liberty." Blake scholar Max Plowman finds in The Marriage of Heaven and Hell the synthesis of the contrary principles expressed in The Songs of Innocence and The Songs of Experience. Blake states this in his text:

Without Contraries is no progression. Attraction and Repulsion, Reason and Energy, Love and Hate, are necessary to Human existence.

From these contraries spring what the religious call Good & Evil. Good is the passive that obeys Reason. Evil is the active springing from Energy.

Here Blake equates God, Heaven and the principle of Good with reason ; Satan, Hell, and the principle of Evil with imagination and poetic inspiration. In a break with his earlier espousing of the doctrines of Emmanuel Swedenborg, Blake advocates the restoration of forceful energy (whether good or evil) in a world dominated and sometimes corrupted by reason. The title itself gives evidence of a response to Swedenborg's Heaven and Hell.

As in all of Blake's best work, the twenty-seven plates of The Marriage of Heaven and Hell reinforce and interpret his text. While Blake's illustration for his opening "Argument" may at first glance seem to be painting an idyllic scene, with couples lolling on the grass and a man handing fruit from a tree to a woman on the ground, Blake's text indicates a different, more threatening world:

Now the streaking serpent walks

In mild humility.

And the just man rages in the wilds

Where lions roam.