From Canon O'Hanlon's Lives of the Irish Saints for 6th February:
- Reputed Festival of St. Melcu or Moelchuo, Supposed be a Bishop of Ardagh.
If we are to credit some records, at this date should we add the festival of a St. Melchu or a St. Moelchuo, thought by many to have been the brother and the inseparable companion of St. Mel. The Martyrology of Salisbury commemorates, at this date, four brothers, St. Mel, St. Melchuo, St. Munis, who are called bishops, and St. Rioch, called an abbot. They are said to have been distinguished for sanctity, and for many miracles. On the date, contained in such entry, Colgan confesses himself induced to place the festival of those reputed brothers, at the 6th of February; although, he says it is possible, St. Melchuo may be identified with St. Mellan, whose festival was observed on the 28th of October, in the territory of Hibh Echach, in Ulster. Other writers have followed Colgan's arrangement; among these may be noted Bishop
Challoner, and Rev. S. Baring-Gould. Ancient tracts have also distinguished St. Mel from St. Melchuo, a reputed brother. Ware and Colgan are said to have been led astray by these accounts, but they are corrected by Dr. Lanigan. Both Mel and Melchus are represented as having been left, in Southern Teffia, by St. Patrick, and as jointly ruling over the see of Ardagh. The day of their festivals is the same—a circumstance rather singular, and suspicious — being reputed brothers, as co-bishops, likewise, in one and the same see. Without sufficient authority, Ware and Harris place Melchuo after Mel, in the order of succession. These names and notices are applied, it is thought, to one and the same person; the real etymon, which was probably Melchu, having been contracted, and Latinized into Melus or Mel, signifying "honey." Hence a false distinction of persons may have arisen.
St. Melchu — it has been asserted — was an assistant to St. Mel, during his missionary labours and preaching. It is thought, too, that Melchu had been consecrated bishop, by his reputed uncle, St. Patrick; and that, he remained with his reputed brother Mel, in the monastery, at Ardagh. They are supposed to have been emulous of each other, only in sanctity, and that Maelchu, having thus persevered to the end, deserved to be registered among the saints. It is not probable, that Tirechan would have omitted to mention Melchu, in addition to Mel, had the former name belonged to a brother of Mel, and to a joint-administrator, at Ardagh. Nor is it likely, the name of Melchu should have been omitted, in our most authentic Irish Martyrologies and Annals, while particular mention is made of Mel or Melus. Labouring under a mistake, Colgan distinguishes St. Melchuo from St. Mel. He devotes a separate short notice to the former, after having given St. Mel's
Acts in full, at the 6th of February. For his various illustrations and proofs, reference is made to these Acts.