The church of Glendaeruel is called Kilmodan, probably representing Cill M’Áedháin in Gaelic, ‘the church of St M’Áedhán. This name is a hypocorism (a kind of devotional nick-name or term of endearment) based on the name Áed (‘flame’) or Áedán (‘little flame’).
It is not clear who the bearer of this name was in relation to the church of Kilmodan in Glendaruel. The Aberdeen Breviary, published in 1510, collects various late medieval saints’ legends, and tells stories about Sanctus Modanus (who may or may not be the same saint as the one culted in Cowal). On 4th February the Breviary offers a prayer:
‘Almighty and everliving God, look kindly on the feast of this day, and by the prayer of St Modan your confessor and abbot, make your church ever rejoice in its celebration, that you may fulfil the prayers of all who believe in you.’
There follow readings about Modan’s life as ‘the father of many monks’, the holiness and austerity of his life, his voluntary poverty, and his successful preaching to the race of the Scots. It states that he preached ‘on the west side of the River Forth … and at Falkirk’, and finally he went ‘to the oceans of Scotland, not far from Dumbarton and Gareloch in a place cut off from from association with all men, in a place surrounded by sea and high mountains’. There ‘shining in many miracles, he fell asleep in the Lord. And in that place the parish church of Rosneath stands, dedicated in his honour, and there his most holy relics rest and are venerated with the utmost devotion in a certain chapel in the cemetery of that church.’ The church in question is not far from Cowal, on the Rosneath peninsula, 25 km east of Kilmodan in Glendaruel (the medieval church of Rosneath was at NS253831).
The Aberdeen Breviary records another cult of St Modan (14th November) ‘who is held in great veneration at Philorth’ (near Fraserburgh in the north-east of the country), but this may actually be the same saint as Modan of Rosneath who was honoured at Philorth on a different day of the year for some reason. The feast-day of Modan of Philorth has no special readings in the Aberdeen Breviary, but only a prayer which is very like the prayer on 4th February except that it makes him a bishop (episcopus) rather than an abbot.
The cult of a St Modan was also celebrated at Falkirk and at Fintray in Aberdeenshire where his feast was on 4th February and where another source states that his relics (or some of them) were kept. There was a chapel of St Modan at Canisbay in Caithness, and at Dryburgh Abbey, and at Airlie in Angus (where there was also a bell which served as a relic). The same saint’s name may appear in a slightly different hypocoristic form in St Madoes (Sanctus Modocus and similar) in the Carse of Gowrie in the east of the country.
Irish and Scottish sources mention many saints called Áed, Áedán, M’Áedán or M’Áedóc – all variants of the same fiery name. It is too much to hope for now that any clarity about the saint culted at Kilmodan in Glendaruel will emerge from the confusion of such sources.