Is Brother David's treatment not a serious one? Or did you mean secular, in the sense that a non-secular treatment cannot be serious?
I'm not sure what the idea is for which you seek a "serious exploration". Such stories are allegories, analogies and metaphors dwelling more in the domain of fictional literature than in serious history (i.e. demonstrable historicity of a folk tale being deliberately modeled on historical fact.) However, ever since Calvert and Schliemann followed Homer to Troy, this point has been rather moot.
Some random thoughts follow.
Clerics and Dwarves - The idea of clerics expressing humility by comparing themselves to dwarves was definitely alive and well in the time of Bernard of Chartres who is said to have died c. 1124. His student John of Salisbury reportedly wrote:
Bernard of Chartres used to say that we are like dwarves perched on the shoulders of giants, and thus we are able to see more and farther than the latter. And this is not at all because of the acuteness of our sight or the stature of our body, but because we are carried aloft and elevated by the magnitude of the giants.
The dwarf analogy has been in circulation ever since, paraphrased in 'serious' writing by the likes of Peter of Blois, Isaac Newton, Samuel Taylor Coleridge, and Stephen Hawking. Its origin with Bernard is also debatable.
Symbolism of Seven - As for the applications of the number seven in monastic, clerical and theological symbolism, the possibilities abound:
- Seven (six plus one) days of creation in Genesis,
- Seven first books of the Bible - the Heptateuch in Augustine's usage.
- Seven sapiential books of the Bible.
- Seven Liberal Arts
- Seven Deadly Sins
- Seven Virtues
- Seven 'hours' of the divine office in Benedict's Rule (Matins, Prime, Terce, Sext, None, Vespers, Compline)
I'm sure you can think of more.
Grimm Sources - My sense of the brothers Grmm's sources is a long history of folk tales and oral transmission. I know of no specific scholarly study on Snow White in particular. Do you suppose their tale is really a disguised or corrupted history of some real heiress, protected or raised in isolation by monks, until her coming of age and accession to her rightful inheritance, or something of the sort? Considering the bloodthirsty machinations of succession most evident within aristocratic lineages throughout European history, such a thing ought not be too surprising. However, I know of no specific case on which the tale might be modelled. Might families facing uncertain futures possibly have found it wise to instruct youngsters with tales of this kind to equip them with ideas, alternatives and the wherewithal to overcome likely adversities of disputed succession the youngsters might need to face alone? Considering the short life expectancies in antiquity and medieval times, second, third and fourth marriages were common. Early widowhood, death in childbirth, plagues, wars, and so on would have led to many youngsters having multiple step-relatives all vying for the same limited store of prizes. Not to mention pretenders, usurpers and inordinate abundances of neglected bastards scattered across the countryside. Is this the idea you'd like to see more seriously explored?
Comparables - The Merlin and Arthur stories might provide good comparables more well covered in the 'serious' literature. Arguably, even Hamlet fits this mold.
Cheers,
Richard.