The use of patristic texts was tightly bound up with the needs of the contemporary discussion which provided Grotius with sources for his patristic citations. His use of ancient texts especially in Ordinum Hollandiae ac Westfrisiae pietas proved to be highly controversial.
Grotius's advocacy of tolerance with respect to various forms of Christianity determines his use of patristic texts as well. He looks for examples of moderation in the Early Church and by this accomplishes a significant shift of perspective. He points out the diversity of expressions in the Early Church and therefore replaces questions of dogmatic definition with the question of how to handle orthodoxy and heresy in society. In doing so, he implies requirements for the proper reading of patristic texts in his own times. Grotius's notion of Christian liberty is connected to awareness of context and intrinsically linked to a historical understanding. In his writings, contextualisation involves both religious-historical comparison and the integration of general sources from antiquity. With regard to early Christian sources, this means that Grotius understands them as deeply rooted in the broader ancient context. This approach to early Christian literature is already visible in De Iure Praedae. His sensibility for cultural variation, his comparative method and historical interest in ancient institutions are outstanding, and Grotius has these characteristics in common with legal humanists like François Baudouin.