This paper aims at showing that the original tension between Christianity and the Law, represented by the Traditio legis motif in early Christian art, is assumed by the thirteenth century theologians not only in their dialectic conception of the relationships between Old et New Testaments, but also in the scholastic working out of Christian norms grounded on Old-Testament precepts such as those imposing Sabbath observance or the paying of tithes. In a general way, they show the specifi c role of the masters in “fulfi lling” the Law, as initiated by Christ; in a more particular way, they also show the strong interweaving of theology and canon law which can be observed in the theological deconstruction and recasting of the obligation of paying tithes.