Institutes of Justinian in the context of "Code of Justinian"

The Novellae Constitutiones ("new constitutions"; Ancient Greek: Νεαραὶ διατάξεις, romanized: Nearaì diatáxeis), or Justinian's Novels, are now considered one of the four major units of Roman law initiated by Roman emperor Justinian I in the course of his long reign (AD 527–565). The other three pieces are: the Codex Justinianus, the Digest, and the Institutes. Justinian's quaestor Tribonian was primarily responsible for compiling these last three. Together, the four parts are known as the Corpus Juris Civilis. Whereas the Code, Digest, and Institutes were designed by Justinian as coherent works, the Novels are diverse laws enacted after 534 (when he promulgated the second edition of the Code) that never were officially compiled during his reign.

The Digest (Latin: Digesta), also known as the Pandects (Pandectae; Ancient Greek: Πανδέκται, Pandéktai, "All-Containing"), was a compendium or digest of juristic writings on Roman law compiled by order of the Byzantine emperor Justinian I in 530–533 AD. It is divided into 50 books.

The Digest was part of a reduction and codification of all Roman laws up to that time, which later came to be known as the Corpus Juris Civilis (lit. 'Body of Civil Law'). The other two parts were a collection of statutes, the Codex (Code), which survives in a second edition, and an introductory textbook, the Institutes; all three parts were given force of law. The set was intended to be complete, but Justinian passed further legislation, which was later collected separately as the Novellae Constitutiones (New Laws or, conventionally, the "Novels").

The scholars of the 11th- and 12th-century legal schools in Italy, France and Germany are identified as glossators in a specific sense. They studied Roman law based on the Digesta, the Codex of Justinian, the Authenticum (an abridged Latin translation of selected constitutions of Justinian, promulgated in Greek after the enactment of the Codex and therefore called Novellae), and his law manual, the Institutiones Iustiniani, compiled together in the Corpus Iuris Civilis. (This title is itself only a sixteenth-century printers' invention.) Their work transformed the inherited ancient texts into a living tradition of medieval Roman law.

The glossators conducted detailed text studies that resulted in collections of explanations. For their work they used a method of study unknown to the Romans themselves, insisting that contradictions in the legal material were only apparent. They tried to harmonize the sources in the conviction that for every legal question only one binding rule exists. Thus they approached these legal sources in a dialectical way, which is a characteristic of medieval scholasticism. They sometimes needed to invent new concepts not found in Roman law, such as half-proof (evidence short of full proof but of some force, such as a single witness). In other medieval disciplines, for example theology and philosophy, glosses were also made on the main authoritative texts.