One of those cool tropes is the use of voces magicae - magical words. In the various cultures of the ancient world it was common to borrow powerful names and formulae from the area's cultures, and employ them rather mechanically as sources of magical strength and authority. The eclectic 1st-century-bc mage would conjure by Osiris, Hecate and Adonai if it brought him the result he sought. Other sorts of magical verbal formulae were apparently constructed by using the letters of one's sacred alphabet symbolically, to create long strings of vowels or compound words and names, anagrams, etc.
http://www.historyofmagick.com/?p=25
From the other end of the Indo-European range, the Vedic spiritual practice of mantram amounts to 'magic words' in those systems. Mantras are generally actual sentences in Sanskrit expressing some mythic symbol or simply listing the names or attributes of a deity. They are often brought into effect by multiple repetitions, often accompanied by offerings, hand or body positions, and other symbolism.
Even in northern heathenry we find the practice of galdor - the singing or intoning of sounds based in the Runes - to accomplish various magical goals. We also here of the vardhlokkur - the song sung to draw the spirits to the seer's high seat in the seidh rite. It's plain that northern tradition valued both abstract, non-word expressions of power as well as verse and meter in magical work.
So, as we approach a Druidic practical magic, how can we bring some of this juice into our work? There are a couple of hints of the use of 'nonsense' syllables in Gaelic folk-magic. The famous 'Fith Fath' spell uses such syllables, as do other Scots charms in Carmichael. These seem to me to participate in the syllable-set of mouth music, but if they ever had an esoteric or symbolic meaning that is lost today. Of course that doesn't mean we couldn't employ them in magic - meaninglessness doesn't mean they are powerless.
We might also mention the notion of using the antique Celtic languages as a source of magic words. Of course many reconstructionists would point out that simply having the skill to speak one's charms in the native tongue of a Celtic people should bring a good charge of might. For those of us with less skill we might still resort to books on Old Irish to find words that might be used in various ways in spells and works.
For the sake of experiment I have decided to take a different approach. We know how much the Celts valued poetry as a source of magical power. There's no argument about the power of poets in Gaelic society to bring luck or ill, and otherwise display 'magic' powers. So I've been crafting some very simple charms that employ a spoken spells written either in tightly composed rhyme and meter, or using some of the motifs of repetition and patterning we see in translated Gaelic charms. Those of us who have spent a while re-Paganizing charms from the Carmina Gadelica have tended to arrive at a style influenced more by Carmichael's translations than by the original Gaelic. The originals are almost all in rhyme and meter and, while this may go against the grain of the sort-of declamatory style that 'Druids' tend to seek, does express an essentially Celtic tradition. So I've decided that tightly woven rhyme and meter, or any well-composed poetry, has a degree of intrinsic magical influence. The will is turned into 'magic words' by being expressed in beauty, balance and order, so that it simply becomes true in the balance and order of the world.
Below is a spell composed in this way - I'm rather proud of its structure and internal rhyme.
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