The work is a contribution to the foundations of the European private law tradition. Its subject is the Digesta of Publius Alfenus Varus (consul in 39 BC), the oldest work of Roman jurisprudence excerpted for the Justinian Digest. The study aims to determine the character of the work and the forms of presentation of this legal text, to establish the origins of the legal material processed, as well as the manner and purpose of its treatment, and, not least, to reconstruct the textual history of the work from its writing to its use by the jurists of Justinian. The means of investigation is the philological and legal analysis of essentially all fragments in their context. The exegesis of a representative selection of the preserved decisions thus forms the core of the work. In the dogmatic context, these decisions are significant.