Having written the aforementioned verse at the end of the page, the saint went to the church to the nocturnal vigils of the Lord’s Day; and so soon as this was over, he returned to his chamber, and spent the remainder of the night on his bed, where he had a bare flag for his couch, and for his pillow a stone, which stands to this day as a kind of monument beside his grave. While then he was reclining there, he gave his last instructions to the brethren, in the hearing of his attendant alone, saying: “These, O my children, are the last words I address to you that ye be at peace, and have unfeigned charity among yourselves; and if you thus follow the example of the holy fathers, God, the Comforter of the good, will be your Helper and I, abiding with Him, will intercede for you; and He will not only give you sufficient to supply the wants of this present life, but will also bestow on you the good and eternal rewards which are laid up for those that keep His commandments.” Thus far have the last words of our venerable patron, as he was about to leave this weary pilgrimage for his heavenly country, been preserved for recital in our brief narrative. After these words, as the happy hour of his departure gradually approached, the saint became silent. Then as soon as the bell tolled at midnight, he rose hastily, and went to the church; and running more quickly than the rest, he entered it alone, and knelt down in prayer beside the altar. At the same moment his attendant Diormit, who more slowly followed him, saw from a distance that the whole interior of the church was filled with a heavenly light in the direction of the saint. And as he drew near to the door, the same light he had seen, and which was also seen by a few more of the brethren standing at a distance, quickly disappeared. Diormit therefore entering the church, cried out in a mournful voice, “Where art thou, father?” And feeling his way in the darkness, as the brethren had not yet brought in the lights, he found the saint lying before the altar; and raising him up a little, he sat down beside him, and laid his holy head on his bosom. Meanwhile the rest of the monks ran in hastily in a body with their lights, and beholding their dying father, burst into lamentations. And the saint, as we have been told by some who were present, even before his soul departed, opened wide his eyes and looked round him from side to side, with a countenance full of wonderful joy and gladness, no doubt seeing the holy angels coming to meet him. Diormit then raised the holy right hand of the saint, that he might bless his assembled monks. And the venerable father himself moved his hand at the same time, as well as he was able that as he could not in words, while his soul was departing, he might at least, by the motion of his hand, be seen to bless his brethren. And having given them his holy benediction in this way, he immediately breathed his last. After his soul had left the tabernacle of the body, his face still continued ruddy, and brightened in a wonderful way by his vision of the angels, and that to such a degree that he had the appearance, not so much of one dead, as of one alive and sleeping. Meanwhile the whole church resounded with loud lamentations of grief.
– St. Adomnán’s Vita Columbæ, Book III, Chapter 24.