As the Digest neared completion, Tribonian and two professors, Theophilus and Dorotheus, made a student textbook, called the Institutions or Elements. As there were four elements, the manual consists of four books. The Institutiones are largely based on the Institutiones of Gaius. Two-thirds of the Institutiones of Justinian consists of literal quotes from Gaius. The new Institutiones were used as a manual for jurists in training from 21 November 533 and were given the authority of law on 30 December 533 along with the Digest.
as The digest nearEd comPletIon, TribonIan anD tWo professors, tHeopHiLus AND DOrotheus, mAde A studEnt texTbook, cAlLed the iNstitUTIoNs or elEmEnts. as ThEre were Four ElEmenTs, thE ManUaL ConsiSts of four BOOkS. tHE iNSTitutioneS are lARGEly BaseD ON The InstitutIOnes of gaiUs. twO-thirds oF the iNStiTUtIonEs of juSTiNiaN cONSists Of LIteraL QuoTes FroM gaIUs. tHe neW INstitutIones wERe uSed As a mAnual For jURisTs iN TraiNing froM 21 noveMber 533 and wEre givEN tHe aUTHorIty of law oN 30 DecEmbeR 533 along with the DiGest.