Reginnaglar

Reginnaglar (singular reginnagli) is a word occurring twice in Old Norse. Its meaning is unclear but it is a compound of reginn, "powers/rulers/gods/sacred" and naglar, "nails". Despite its rarity, the word has occasioned quite extensive scholarly debate because it may give insight into Norse mythology.

The first attestation is in a rather cryptic kenning in stanza 10 of the skaldic poem Glælognskviða by Þórarinn loftunga, thought to date from 1030×34. In it Þórarinn advises King Svein Knutsson of Norway, encouraging him to pray to his predecessor, Olaf II of Norway; the poem is among our earliest evidence for Olaf's status as a saint in Norway. One of the exhortations to Sveinn to pray runs

which appears literally to mean 'when you perform/present your prayers in front of the sacred nail(s) [reginnagla] of the language/speech/measure/inlaid decoration of books'. The main interpretations of the phrase 'reginnalga bóka máls' have been:

Of these, 'Olaf' has historically been the most common and 'liturgical book', suggested by Margaret Clunies Ross, the most recent (as of 2014).

The other attestation of reginnaglar is in the Icelandic saga Eyrbyggja saga, which relates the use of reginnaglar in the construction of a temple by Þórólfur Mostrarskegg (Thorolf Most-Beard):

Here the nails clearly represent some kind of metal, nail-like decorative feature of the high-seat pillars, and Clunies Ross sees it as plausible that despite the lateness of the source, it does represent a feature of pre-Christian material culture.

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