In Castile, as in the rest of Europe, the jurists of the sixteenth and seventeenth centuries used the qualifiers civil and natural for the classification of both obligations and possessions. The legal situations defined by personal rights and rights in rem gave rise to the interpretation of the coincidences and differences that those labels implied, and to the assessment of the way in which positive law channelled factors of a moral or theological nature into the tensions generated in practice by patrimonial legal relations.