In the space of a few sentences in Proteus, Stephen manages to associate himself both with Christ ("Come. I thirst") and with Satan ("Clouding over. No black clouds anywhere, are there? Thunderstorm. Allbright he falls, proud lightning of the intellect, Lucifer, dico, qui nescit occasum"). In terms of his personal mythologizing, this makes sense: both figures appeal to Stephen, as they did to Joyce. There is also some connection in the name Lucifer, which can apply to both Christ and Satan.

John Hunt 2016

Gustave Dore's depiction of the fall of Lucifer, in an illustration of John Milton's Paradise Lost (1866). Source: Wikimedia Commons.

Dark skies in Christ on the Cross, an oil on copper painting by Carl Heinrich Bloch (1870), held in the Museum of Natural History, Denmark. Source: Wikimedia Commons.