Gratian, Roman Law, and the Role of Consent

ln, Erzbischfliche Dizesan- und Dombibliothek 127, fol. 10r

Gratian, D.4 dictum after c.3:   Ordinances (Leges) are instituted when they are promulgated;  they are confirmed when they have been approved by the mos of those who observe them.  Just as indeed the several laws (leges) today are abrogated by the mos of those who observe them (interlinear gloss: completely taken away: penitus ablate).


Florence, Biblioteca Laurenziana Santa Croce 1 sin. 1 fol. 6r

D.12 c.6 (Justinian's Institutes 1.1):  Long standing usages (mos) approved by the consent (consensus) of those following them are like ordinances (lex) (Diuturni mores consensu utentium approbati legem inmitantur).