Dictionary of National Biography, 1885-1900/Muirchu Maccu Machtheni
MUIRCHU MACCU MACHTHENI, Saint (fl. 697), is termed in the 'Martyrology of Donegal' Mac ua Maichtene, and in the 'Lebar Brecc' Mac hui mic Teni, i.e. son of the grandson of Mac Teni. Bishop Graves suggests that the name Machtheni is a translation of Cogitosus, who mentions Muirchu as his father; the word is cognate with machtnaigim, 'I ponder.' Maccu Machtheni would thus mean 'of the sons of Cogitosus.' Colgan and Lanigan were disposed to identify him with Adamnan, who is known as Ua Tinne, but the resemblance of the names is only apparent. His monastery (civitas), according to the 'Lebar Brecc,' was in Hy Faelan, in the north of the county of Kildare, but the 'Calendar of Cashel' says Gill Murchon (Murchu's Church) was in Hy Garchon in the county of Wicklow.
Muirchu is only known as the author of the life of St. Patrick in the 'Book of Armagh,' a manuscript transcribed in 807, and now preserved in Trinity College, Dublin. This is the earliest existing life of the saint, and forms the foundation of all the later lives, which either borrow from it or enlarge on it. It was composed in obedience to the command and at the dictation of Aedh of Sletty in the south of the Queen's County, an anchorite and bishop, who appears to have been specially interested in the see of St. Patrick, and was intimately associated with Adamnan in endeavouring to introduce the Roman Easter and other foreign customs in the North. Muirchu, who was with Adamnan at the synod summoned to support the new customs over which Flann Febla, coarb of Armagh, presided, supported the innovation. He tells us that 'many had taken in hand' the life of St. Patrick, but had failed owing to the conflicting nature of the accounts then current and the many doubts of the facts expressed on all sides. He uses the 'Confession of St. Patrick' as his authority for the earlier part, and then proceeds to the traditional matter. The parts do not harmonise, but his work is of great importance, as identifying the author of the 'Confession' with the popular saint. The copy of this life in the 'Book of Armagh' was imperfect for more than two centuries owing to the loss of the first leaf, but a few years ago the Bollandist fathers found in the Royal Library of Brussels a Legendarium of the eleventh century which contained a perfect copy of the life, not taken from the Armagh codex, and in some respects more accurate. This was placed in the hands of the Rev. Edmund Hogan, S. J., by whom it was carefully edited and published in the 'Analecta Bollandiana' in 1882. Muirchu's day is 8 June.
[Vita Sancti Patricii; Analecta Bollandiana; Brussels, 1882, p. 20; Lanigan's Eccl. Hist. iii. 131; Martyrology of Donegal, p. 41; Calendar of Oengus, p. xcix; Adamnan's St. Columba, ed. Reeves, Appendix to Preface, p. 41; Goidelica, by Whitley Stokes, 2nd ed. p. 92.]