During the period of Christian conversion of Ireland in the 4th and 5th centuries, it was the strategy of monastic scholars to ensure an easy transition from Celtic to Christian belief. The disciples of Saint Patrick successfully deceived the Celts into thinking that the new faith of Rome was a mere extension of their traditional religion.
Christian missionaries incorporated elements of the peoples veneration of the Celtic Gods into Christian doctrine. The often used example of this religious shift is the fate of Brigid. Brigid was deftly transformed from a daughter of ‘The Dagda’ of the Tuatha Dé Danann into the Saint of the same name. In the early tales of the Christian Saint, Brigid is portrayed as the daughter of a Druidical household before her embrace of the new religion. The Druids were the priests of the pagan Celtic religion but were also akin to today’s upper middle classes: “The Druids were the professionals of pre Christian Celtic society. They comprised all the professions – doctors, lawyers, teachers, philosophers, ambassadors...(and priests of the Celtic Faith)” (Ellis). Thus with her conversion to Christianity, Brigid abandons the Celtic Gods and their priests, the Druids. To reinforce this transition the early church adopted the feast day of the Celtic Goddess Brigid, or Imbolg, to the feast day of the Christian saint.
Imbolg, observed on the first day of February, is the second of the four ancient yearly Celtic Festivals, representing the advent of the traditional agricultural year. It is a pastoral holiday marking the start of the lactation of domesticated sheep, an important annual milestone to the pastoral Celt. Imbolg is connected with the Celtic goddess Brigit because Imbolg is the same day as the Festival of the Goddess Brigit. The exact same day.
Christians recognise Brigit as an Irish Saint, second only to St. Patrick and ranking with St. Columba. But the pagan deity of the same name had a much wider influence. There is archaeological evidence of the Celtic Goddess Brigit being worshipped not only in the modern Celtic nations but in pre-Roman continental Europe during the period of Celtic cultural hegemony, a time when the Celts held sway from the British Islands to the Black Sea. Patricia Monaghan in "The Encyclopaedia of Celtic Mythology and Folklore" continues on the same line:
As goddess, Brigid is a rarity among the Celts, a divinity who appears in many sites. Her name has numerous variants (Brigid/Brigit/Brid/Brighid). As Celtic divinities tended to be intensely place bound, the apparently pan-Celtic nature of this figure is remarkable. The Irish Goddess ruled transformation of all sorts: through poetry, through smith craft, through healing. Associated with fire and cattle, she was the daughter of the (immensely powerful) god of fertility, the Dagda.
Thus emerges the picture of Brigid, the Exalted One, a majestic deity who spanned the Celtic world at its most powerful. A deity that Christian Monks who, upon their penetration of the Celtic homelands in the 6th century after the collapse of the Roman world, could not ignore. So they set about transforming Brigid, the “Exalted One” of the Celtic pantheon, and the daughter of Dagda, to a Christian Saint to be used as a potent weapon in their war on the pagan beliefs of the Celts.
It is arguable that nothing typifies more the successful tactics of the Christian conversion of Ireland than the fate of Brigit, the daughter of Dagda (a principal god of Celtic mythology). One is tempted to weep to imagine how she suffers having spent the past 1600 years confined to the rigid confines of the Christian liturgy. To promote their new religion, a new and confusing theology to the Gael, the soldiers of St. Patrick transformed Brigit into a Christian rather than a Celtic deity
Miranda Green in her work the Dictionary of Celtic Myth and Legend characterises the transition from Celtic Goddess to Christian Saint:
The name of the Irish goddess was originally an epithet meaning "exalted one". Brigit is of special interest because she appears to have undergone a smooth transition from Pagan Goddess to Christian Saint. As a saint, Brigit took over many of the attributes of the pagan goddess. Her birth and upbringing were steeped in magic. She was born in a Druid’s household and fed on the milk of magical, Otherworld cows. As a Saint of Kildare her fertility symbolism is intense, even though she herself was a virgin. She supplied limitless food without her larder ever dwindling; she could provide a lake of milk from her cows. But the most significant factor in the transition is that the feast day of St. Brigit took place on 1 February, Celtic feast of Imbolg, which was the Festival of Brigit the goddess.
However, the elimination of Celtic pagan religious practices proved a daunting task, so much so that the 7th century Pope Gregory was prompted to decree:
Take advantage of well-built temples by purifying them from devil worship and dedicating them to the service of the true God.
And it was in this spirit that the shrine at the Kil Dara (the temple of the oak), a pagan sanctuary built from the wood of a tree sacred to the Druids and which was dedicated to the Celtic Goddess was changed into a Christian shrine. The ritual fire of the Druids, which honoured Brigit, was extinguished and a new flame lit in deference to the Christian Saint. Thus the disciples of Saint Patrick adopted the pre-Christian practices of the Celts so that the new religion was viewed as a continuation of their ancient beliefs.
There are four great Feast Days of the Celtic Year:
Patricia Monaghan's "The Encyclopedia of Celtic Mythology and Folklore"
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