Laisrén mac Nad Froích

Laisrén mac Nad Froích, known in later devotion as Saint Laserian or Saint Molaise of Leighlin, was an Irish abbot and bishop of the early seventh century and the principal saint of the monastery of Lethglenn, now Old Leighlin in County Carlow. His patronymic identifies him as the son of Nad Froích. Genealogical tracts connect that father with the Uí Bairrche, a people of southern Leinster whose territory lay in the region of the later diocese. A separate and less credible strand of hagiography makes him the son of an Ulster noble named Cairel and of Blitha, and sends him as a youth to Munster or to Scotland. No annal or early calendar records his birth year or birthplace; he can only be placed in Ireland in the later sixth century. He is not to be confused with other early Irish saints of similar name, including Laisrén of Iona, Molaise of Devenish, and Molaise of Inishmurray.

Almost nothing of his career is documented by contemporary evidence. The earliest firm notice is the record of his death in the Irish annals. Medieval lives, written centuries later, describe a monastic formation in Ireland, a sojourn among the Columban communities of Britain or Iona, and one or more journeys to Rome. In that legendary outline he is ordained priest, sometimes by Pope Gregory the Great, and subsequently consecrated bishop by Pope Honorius I, who is said to have named him a papal legate for Ireland. These Roman episodes cannot be confirmed, but they reflect a real historical context. In the 620s and 630s the southern Irish churches moved toward the Roman calculation of Easter. Pope Honorius I wrote to the Irish on the subject, and around 632 the scholar Cummian addressed a letter defending the Roman computus after a delegation had gone to Rome. Later tradition cast Laisrén as a leader of the Roman party and as a speaker at a synod held at Magh Lene (Campus Lene). Whether he took part in that synod is unknown; that he belonged to the southern Irish ecclesiastical world that accepted the Roman Easter is consistent with his date and locality.

Leighlin, whose Irish name Lethglenn is interpreted as half-valley or grey glen, became his chief foundation. Some accounts hold that Saint Gobban first gathered a community there and that Laisrén succeeded him as abbot; others treat Laisrén as founder. Under his name the monastery grew into a major church of Leinster. Medieval writers give inflated figures for the number of monks, which cannot be taken literally, but they attest to the later prestige of the house. Laisrén is remembered both as abbot and as bishop. The Annals of Ulster, in recording his death, call him abbot of Leighlin rather than bishop, which may indicate that episcopal status was attached to the monastery in the Irish manner, or that the episcopal title is a later development of the cult. From this community descended the medieval Diocese of Leighlin. The present Church of Ireland cathedral of Saint Laserian at Old Leighlin occupies the traditional site, and a holy well nearby has long been associated with the saint.

According to the Annals of Ulster, Laisrén, abbot of Leighlin, died in 639. Irish martyrologies, beginning with the Martyrology of Oengus in the early ninth century, keep his feast on 18 April, which became the standard date in both Irish and later Catholic calendars. He was honoured as a saint by local and national cult in the centuries after his death; there was no medieval papal canonization. His patronage remains that of the historic Diocese of Leighlin, since the late seventeenth century united with Kildare as the Diocese of Kildare and Leighlin. Beyond the annalistic death-notice, the martyrological date, the genealogical affiliation with the Uí Bairrche, and the enduring association with Old Leighlin, the particulars of his life rest on late and uncritical hagiography and should be treated with caution.