(To part 4)
Celtic culture was built on a trinity, a triad. So they did not assume a duality of light and dark, of white and black, but 'the middle' was important to them. The dawn and dusk were spiritual times. The many 'nature gods', the elemental beings, appeared in triplicate. Their riddles, the way in which spiritual knowledge was passed on, always had a threesome.
A poem where the triad is expressed is the following. The three joys of the bards of Britain are:
speak with expertise;
act with wisdom;
bring peace and harmony.
The druids who led their students passed on their knowledge through triads. Nothing was put in writing! Everything was transmitted orally and to facilitate this often in melodious, poetic triads transmitted in thousands of verses.
The trinity is also expressed in their divine principle and the druids proclaimed a teaching whereby everything returns to God again.
One is the number of eternal immutability and is in all, as all is in Him. Two is the number of diversity, of inconstancy, because everything in turn emerges in its opposite. Three is the perfect number, it dissolves the contradictions and gives relief.
There are three original units for the Druids:
one point of freedom.
Furthermore, three things come out of these original units:
all the good,
The disciples of the Druids were taught and encouraged to master these things: high morals, purity of manners and customs, impeccable conduct, great liberty of mind, independence in judgment, lofty principles, and a desire to spirituality.
All this was furthered by the following triad:
worship the deity,
working for the world and humanity,
bravely endure the blows of fate.
Celtic society was also divided into three parts. In addition to the common people, three classes were distinguished: the warriors with the kings, the druids with their priests and judges, and finally the bards, including singers and doctors. This division into three also immediately indicated the situation in which man stood: the unfree, the free and the noble.
This is made clear in a verse in the Edda, the Northern mythical stories. In the myth of 'The Song of Rig', Rigspula is the god of the Aesir. When Rig travels around he meets three childless parents and fathers a son with the three women.
The poet was able to indicate the three positions in a poetic but very specific way. This poem is estimated by Jan de Vries  around the 12th century. Here are some excerpts.
Among the unfree the son is called Servant:
She bore a son,
brown in skin;
they baptized the boy,
and Servant was his name.
Among the freemen the son is called Karl:
She bore a son,
white in skin;
they baptized the boy
and Karl was his name.
Finally, among the nobles, the woman bears a son named Jarl:
A son bore Mother,
wound him in silk;
they baptized the boy,
and Jarl was his name;
his hair was pale and his cheeks white,
his eyes are resplendent like a serpent's.
According to Jan de Vries, among the Celts there were a large group of aristocratic youths who were trained by the Druids as warriors to defend the tribe. They were taught how a warrior should behave.
The following triad was favored by these Celtic young men:
Of course, this did not require twenty years of apprenticeship; those who completed this period of time were prepared for the office of priest.
There are three differences that distinguish any human being from another being:
His original mind,
his powers of observation.
Finally, another important triad about the three things necessary to overcome evil:
to bear the blows of fate in silence,
freedom of choice, allowing him to predetermine his own destiny.
Through the use of freedom and choice, man develops three attainments:
The above is of course highly topical at all times!
(To be continued in part 6)
 Atonin Gadal, Het Druïdisme [The Druidism], Rozekruis Pers, Haarlem 2019
 Jan de Vries, De Edda - Goden en heldenliederen uit de Germaanse oudheid [The Edda - Gods and Heroic Songs of Germanic Antiquity], Ankhhermes 2012