Justinian's Institutes was one part of his effort to codify Roman law and to reform legal education, of which the Digest also was a part.[2] Whereas the Digest was to be used by advanced law students, Justinian's Institutes was to be a textbook for new students.[3] The need for a new text for first year students was addressed as early as 530 in the constitution "Deo auctore," where reference is made to something "...which may be promulgated to replace the elementary works, so that the raw intelligence of the student, nourished by a simple diet, may proceed more easily to advanced legal studies."[4] Under the supervision of Tribonian, two law professors (Theophilus and Dorotheus) were assigned to extract statements about the basic institutions ("Institutiones") of Roman law from the teaching books created by writers of "authority" (as defined in the Law of Citations). (Wikipedia)