Lathcen (Laidcenn) (d. 661), son of Báeth Bandach, monk of Clonfertmulloe (Co. Laois) and biblical scholar, produced an abbreviated version of Gregory the Great's ‘Moralia’ on Job, a commentary in thirty-five books, written c.595. Lathcen's abbreviation in three books is faithful to the text and distinguishes between the literal and allegorical senses, but does not take much account of the moral sense. The manuscripts he used were at least 100 years earlier than any now extant of Gregory's commentary; his abridgement is therefore a valuable witness to the text. His abridgement was widely known on the Continent; it was used in the ninth century by Martinus Hiberniensis (qv), master of the school at Laon cathedral. The hymn ‘Suffragare Trinitatis unitas’ is also attributed to Lathcen in some manuscripts. A lorica (breastplate; a prayer for bodily and spiritual protection) written in the ‘hisperic’ Latin style is probably also by him. Apart from his epitome of Gregory's ‘Moralia’, nothing of his exegetical work has survived. Lathcen died on 12 January 661.
An early seventh-century anonymous Irish commentary on the ‘Catholic Epistles’ twice cites Lathcen as an authority. The early ninth-century text of the Martyrology of Óengus (qv) (fl. c.830) described him as ‘one who expounded the mysteries of Christ’. A little later, he was named by the St Gall scholar Notker Balbulus as one of those ‘who expounded the Scriptures with dedication’. In the martyrologies he is designated as ‘learned’ (sapiens) and ‘holy confessor’. In modern times, the scholar Mario Esposito (qv) has claimed, ‘no future editor of St Gregory's treatise can afford to neglect Lathcen's abridgement.’