I offered a few thoughts on the subject a decade ago via my book Of Giants. Note the dated and clunky Lacanian bent. I'd compose these passages quite differently now, but they are an attempt to analyze how some Old English texts imagined the confluence of false gods with a true one.
In the long post-colonial moment that occurred on the island as the Roman church extended the sphere of its epistemological hegemony, Christianitas was continuously promulgated as a unifying principle, as a point of identification strong enough to overcome the constituent differences that kept "Anglo-Saxon" England fragmentary, in order to effectuate a newly totalizing identity. The Two Fathers become part of an ideological fantasy that covers over the radical alterity, the incommensurability, of the northern (pagan) and Latin (Christian) worldviews -- a difference in symbolization so fundamental that it extends all the way to their foundational myths, their cosmogonies. Under the new regime of signs, the Father of Prohibition becomes that divinity who reconfigures the symbolic order through his resounding NO, the Father who cuts off access to the riches of heaven by immuring behind strong walls what treasure it holds. The Father of Enjoyment, on the other hand, is he who for whom enjoyment was once possible, the one prior to or outside of this foundational Law, celebrant of the flesh and the enemy of the divine. Conveniently, that figure is the giant in both traditions, and so this monster was a natural point at which to begin the translation of early northern myth into the exegetical lingua Christianitatis. Within the new symbolization of the ordo mundi precipitated by the meeting of the Latin and northern cosmogonies, both Anglo-Saxon fathers became coincipient, mutually constitutive. Since God and the giants were entwined in a new moment of origin, both figured within a widespread cultural narrative of how the world received its primal ordering. In fact, whenever a problem of origins is approached in early medieval England, the giant lurks nearby, never far from the threshold of whatever architecture is being built in order to erect an interiority against a wilderness, in order to give a human form to history.
Late in the ninth century, King Alfred the Great reworked Boethius' sixth century philosophical treatise De Consolatione Philosophiae (The Consolation of Philosophy ) into Old English prose, the first of two English monarchs to translate the Latin work. His contemporaries may well have found the consolatio promised by the title as they read the work in its new vernacular edition. Medievalists are apt to value it more highly, however, for the insights contained in the numerous glosses to what Alfred considered difficult or obscure passages. For example, the somatic transformations worked by a sorceress in the Odyssey are connected in a short Boethian meter to inner morality and outward appearance. The Latin speaks obliquely of dux Neritii (Ulysses) and pulchra dea solis edita semine (Circe). In the course of explaining the second allusion, Alfred writes:
At that time there was a daughter of Apollo, son of Jupiter; this Jupiter was their king and had pretended that he was the highest god; and that foolish people believed him, because he was of royal blood; and they knew no other god in that time, but worshipped their kings as divine. Thus Saturn, the father of Jupiter, had likewise to be a god, as well as each of his sons. One of these was Apollo, whom we just mentioned. This Apollo's daughter had to be a goddess; her name was Circe.
The explanation does more than elucidate a difficult Latin phrase. It provides a myth of origin for the gods of classical antiquity. The pagan divinities are dismissed as prideful, all too human monarchs and their families, for whom deification is something of a fad: once the man named Jupiter succeeds in convincing his credulous subjects of his immortal blood, his father, sons, and even grand-daughter insist upon their place in the new pantheon. The story validates Christianitas over pagan error while explaining to the curious how anthropomorphic pseudo-divinities entered the world.
The linking of the deities of classical mythology to mortal or demonic impersonators is a commonplace in early theological writing. Justin Martyr in the Apologia and Augustine in De civitate dei were among the many patristic writers to reiterate the belief. Isidore of Seville summarized this exegetical tradition in his influential Etymologiae (VIII.xi), "De diis gentium":
Those whom the pagans worship as gods were once human and lived among men, such as Isis in Egypt, Jupiter in Crete, and Faunus in Rome … They were formerly mighty heroes [viri fortes ], founders of cities; when they died, images were erected to honor them … Persuaded by demons, posterity esteemed these men gods, and worshiped them.
These deceiving viri fortes were first described by the Church fathers as fallen angels, then with a shift in the exegesis they became powerful, evil men, often said to be descended from either fratricidal Cain or Noah's mocking son, Cham. In Anglo-Saxon England, the viri fortes became gigantes. Oliver Emerson argues that the early Christian writers enabled this myth by building on the conflation of the giants of Genesis with the classical stormers of Olympus by the Jewish historian Josephus ("Legends of Cain," 905). No doubt this conjoining was enabled through the moralizing of the biblical giants already well under way by the time of the Jewish apocrypha. The Book of Wisdom characterizes these monsters as corporeal signifiers of overbearing pride, destroyed as a rebuke to that primal sin: "from the beginning when the proud giants perished, the hope of mankind escaped on a raft and .. bequeathed to the world a new breed of men" (14:6). The biblical passage underscores the giants' historicity: these monsters predate the flood, which was sent to cleanse the earth of the evils they embody. By simultaneously reading the body of the giants as allegory, however, the Book of Wisdom suggests a continuity with the giants of classical tradition, likewise condemned as monstrously prideful in their failed attempt to pile Ossa on Pelion in order to steal from the gods the immortal home of Olympus.
After describing the demise of the giants, the passage from Wisdom explains how later in world history "tyrants" devised idols in order to deny the fact of the body's mortality (Wisdom 14:15-21). The story entwines loss (a father mourns his dead son with an image that others worship as a god), pride (despots [tyranni] thinking themselves greater than human order their statues venerated), the alluring power of the visual (the idols elicit awe because of their "ideal form," an artistically induced numinousness), and the reifying power of the law (the longer the idol is worshipped the more natural such action appears, so that through repetition a reality is materialized for divinity). As in the Lacanian Mirror Stage, a jubilant image becomes a trap for the gaze, a lure that catches the unwary subject in an estranging identification -- here, one that produces a false deity rather than an embodied ego.
In the Latin church, wicked men rather than inhuman monsters were invariably held to be those tyranni responsible for the sin of embodying divinity within human corporeality. For Anglo-Saxon writers, however, these primordial deceivers were always the giants. The Book of Wisdom unites the giants and the "despotic princes" only by narrative proximity, but in early medieval England the two episodes in salvation history (the destruction of the giants, the promulgation of idols) became conjoined into a newly hybrid foundational narrative that bridged classical, biblical, and northern traditions. The homilist Ælfric explicates this myth of origin in the Passio Apostolorum Petri et Pauli, as an elucidation of why Peter should have called Jesus "son of the living God" [lifigendan Godes]:
Peter said 'of the living God' to distinguish the lesser gods, who deceived the heathens with various heresies. Some believed in dead giants, and raised up precious images, and said that they were gods because of their great strength; nevertheless their lives were very sinful and unclean.
The giants are an ancient, vanished race whose fossilized remains are not mysterious bones or odd topography, but the lingering worship of their iniquity. The references to constructing idols and deifying the sun and moon which follow make it clear that Ælfric has both biblical and classical deities in mind. By describing the genesis of the false, mortal divinities of the Greeks and Romans (along with those of the Babylonians, Canaanites and wayward Israelites), Ælfric is repeating a connection frequently made in Old English literature between the opprobrious giants of Christian tradition and the gods of classical mythology.
Etiologic myths linking biblical exegesis with Greek and Roman literature were a favorite of erudite Latin culture throughout the Middle Ages. Yet there is something distinctly Anglo-Saxon about this fascination with giants conjoined to the formation of alienated, human identities. In the course of one of the many homilies collected by Napier, a discourse on the early power of the devil over humanity leads to an excursus amounting to a full creation myth for the numerous gods of old:
the devil ruled men on earth, and he strove against God and God's people; and he raised himself over all, so that the heathens said that the gods were their heathen leaders; such a one was the giant Hercules and Apollo, who left the glorious God; Thor also and Odin, whom the heathens greatly praise.
Apollo, the classical pantheon, and even the semi-divine Greek hero Hercules are not the only divinities invented by megalomaniacal giants. Thor and Odin, the most familiar gods of Northern provenance, also become originary entas. Even after the Vanir and Aesir had been replaced by Christian monotheism, traditions of giants lingered. As erudite culture displaced the more indigenous, heathen tradition, this Old Order of giants became conflated with the vanished gods whom they had aided and battled so that both could then be denigrated as deceivers and impersonators, validating the superiority of Christianiatas as a homogenous, erudite, right-thinking culture. The northern, mythographic propensity to utilize giants in a drama of etiology was adapted to the formation of a new scholastic myth through which the Germanic cosmology could be restructured and subordinated beneath a new set of master signifiers.