Benedict de Soxo’s <i>Claves Juris</i> – The First Law Textbook in Vilnius

Abstract Benedict de Soxo, who is sometimes considered one of the best rectors of Vilnius, is the author of a treatise entitled Claves juris , published in 1648. It was the first textbook on the study of law in the Grand Duchy of Lithuania, studied by candidates preparing for utrisque iuris doctorates. The aim of this article is to familiarise contemporary readers with the content of Claves juris . This will not only allow them to learn about the work of the rector of the Vilnius Academy, but also to assess the scientific value of the textbook. The actual content of the work consists of a series of treatises (chapters and subchapters) entitled Claves . The Spanish professor composed Claves juris in such a way that canon law took up more space than Roman (civil) law. The sections devoted to Corpus Iuris Civilis Romanorum were constructed in the form of questions and answers. In this part of the work, the rector of the Vilnius Academy cited only works created as part of the Justinian codification: Digesta, Institutions, Justinian Code and Authenticum – a private collection of Novels from 535–556 AD.