The Glossa ordinaria on the Bible stands as one of the prime achievements of the period in western intellectual history known as the Renaissance of the twelfth century. In spite of the great number of still extant manuscripts very little is known about the circumstances around its composition. This state of affairs is partly explained by the lack of modern and critical editions of the books of the Glossa ordinaria. The present work is the first critical edition of the Glossa ordinaria on the Book of Lamentations, and consists of the forewords, or prothemata, and the first book (of five) of this text, which was compiled early in the twelfth century by the theologian and Ciceronian rhetorician Gilbert the Universal (†1134), schoolmaster at Auxerre and subsequently Bishop of London. The introduction includes a background sketch of the environment in which the Glossa ordinaria was conceived – the school of Laon – with a short biography of Gilbert the Universal, as well as a study of the sources to this particular part of the Gloss, chief among them the ninth-century commentary of Paschasius Radbertus. It is shown that Gilbert’s major improvement to his source, apart from drastically rewriting it, consists of the introduction of Ciceronian rhetorical loci to the verses of Lamentations. The introduction furthermore provides the reader with an analysis of the manuscript tradition of the early twelfth century and a selective analysis of the later manuscript tradition (some 86 manuscripts have so far been traced). One of the conclusions reached is that the Gloss on Lamentations exists in two textual recensions, the one original, the other a later redaction made once the Gloss had become a success and preserved in nearly all the later manuscripts. The manuscripts of the first recension, which is the one edited in the present work, may be organised into a stemma codicum consisting of two major families originating in a single archetype. It is possible to reconstruct this archetype on the basis of the five oldest manuscripts. An English translation of the edited text is included, as well as a ‘semi-critical’ edition of the text of the second recension. An important part of the present work consists of an effort to combine the sophisticated mise-en-page of the glossed manuscripts with the standards of presentation to be expected of a modern critical edition.