The Most Ancient Lives of Saint Patrick/The Life and Acts of St. Patrick/Chapter 125
Nine Evil-doers are consumed by Fire from Heaven, and a Fountain is produced out of the Earth.
And nine evil-doers contriving the death of Patrick, the herald of life, pretended to be monks and ministers of righteousness; and they put on them white cowls, that the easier might they destroy the saint, who was clothed in the same habit. And herein did they imitate their preceptor, Satan, the angel of darkness, who sometimes transfigureth himself into an angel of light, and unto whom in their arts and in their acts they paid obedience. But an illustrious man named Enda, the friend of the holy prelate, observing the treachery of these wicked men, sent unto them his own son named Conallus, that he might prevent their endeavor, and repulse their violence from the man of God. And the son did even as his father commanded, and stood, the son of light, among these sons of darkness. And Saint Patrick, warned of heaven, knew these ravens under the wings of the dove, these wolves under the fleece of the lamb; but well he knew that as the Ethiop cannot change his skin, no, not though washed with fine linen, so could not these magicians quit their inborn wickedness, though clothed in white raiment. Therefore with the sign of the cross he fortified himself, and opposed it to the enemies of Christ; and fire marvellously descending from heaven consumed the evil-doers, and left Conallus standing among them, unhurt of the flame, as he was guiltless of their sin. Thus was the cross of Christ a protection to the faithful even for their salvation, and to the idolaters a punishment even for their perdition. And afterward the saint impressed on the earth the sign of the cross, and a clear and salubrious fountain issued forth. And on the spot where this miracle was worked by the cross did he build a church, which even unto this day is called the Cross of Saint Patrick.