Ireland has also been credited with the doubtful honour of having given birth to Caelestius, the friend and associate of the celebrated heresiarch Pelagius. We believe that notwithstanding the authority of many eminent Irish scholars, we can show that Caelestius was not an Irishman, and that the idea of his being a 'Scot' arose from misunderstanding a passage in the writings of St. Jerome, which passage was the only authority ever alleged in favour of his Irish origin. This celebrated passage is contained in the _Preface to the Saint's Commentaries on Jeremias_. Here it is--"He (Grunnius), though silent now himself, barks by the mouth of the Alban dog, a corpulent and unwieldy brute, better able to kick than to bite, who derives his origin from the Scottish nation in the neighbourhood of Britain."[54] Now so far as we know, this solitary sentence is the only original authority for the Irish birth of Caelestius; yet as a matter of fact it does not appear to refer to Caelestius at all, but to Pelagius himself. Grunnius, to whom the context clearly shows that St. Jerome refers, was a nickname often given by the saint to Rufinus of Aquileia. Rufinus was then (_mutus_) silent, most probably in death, but still barks through his disciple Pelagius--not Caelestius--who in the vigorous controversial language of the saint is described as an Alban or Scottish dog, filled with the porridge of his native country in the neighbourhood of Britain. As a matter of fact, however, Jerome does not say that the person of whom he is speaking was a Scot (whether of Erin or Alba), but that he was of Scottish origin, which is a very different thing. His Words are--"Habet progeniem Scotticæ gentis." He is of Scottish extraction, which might be very well said of Pelagius, even though he were a Briton by birth.