Blake was conflicted in regard to illustrating Dante's Divine Comedy. Although he admired Dante's genius, he deplored much in Dante's theology. Notice that Blake mentioned Dante among various luminaries in a positive role in Jerusalem.
Jerusalem , Plate 73, (E 228)
"And all the Kings & Nobles of the Earth & all their Glories
These are Created by Rahab & Tirzah in Ulro: but around
These, to preserve them from Eternal Death Los Creates
Adam Noah Abraham Moses Samuel David Ezekiel
[Pythagoras Socrates Euripedes Virgil Dante Milton]
Dissipating the rocky forms of Death, by his thunderous Hammer
As the Pilgrim passes while the Country permanent remains
So Men pass on: but States remain permanent for ever"
The line on Plate 73 of Jerusalem mentioning Dante was deleted by Blake after further consideration. Blake had included geniuses of Greek and European literature along with the most influential Old Testament characters, as individuals created by Los to preserve imagination. Apparently Blake later decided that he could not put all of these men in the same category.
When late in life Blake was commissioned to illustrate the Divine Comedy, he went about the task with enthusiasm but skepticism. A particular illustration in which the giant Antaeus transports Virgil and Dante to a lower circle of hell as per their request, gave Blake an opportunity to show a benevolent giant gently placing the two pilgrims on the ledge below. If Blake was making a bit of a joke by picturing an acrobatic giant clinging to the cliftside with an expression of loving concern on his face, some think that Dante too was making a joke with Virgil's negotiations with Antaeus.
Blake produced other pictures contrasting the size of giants with ordinary humans. The Angel of Revelation pictures a vision being recorded by John of Patmos as he sits between the feet of the gigantic angel who commanded him to prophesy. Plate 62 of Jerusalem pictures the agonized giant Albion standing above the diminutive Los, the One who stood forth to warn Albion. The Eternal Zoas were giants too although we don't see them pictured with ordinary humans. In the illustrations to Night Thoughts there is occasionally a contrast between giant figures and ordinary sized ones. Much as Blake in his poetry used words to describe various levels of existence, he used size in images to portray different orders of reality. Becoming conscious of the Gigantic forms represents a mental awakening.
It appears that Blake used the image of Antaeus, Virgil and Dante as a reminder that powerful forces may offer unexpected assistance.