We are accustomed to think of the natural law as being more or less equivalent to a universal morality, whether this is seen as grounded in nature in some general sense, or more specifically in the deliverances of practical reason. There is another way of approaching the natural law, however, according to which it is identified with a specific moral tradition which cannot be adequately understood apart from some account of its historical development and social location. This paper defends the latter approach. It proceeds by way of an examination of one phase in the development of the natural law tradition, namely, its formulation as a systematic moral theology in the early scholastic period. Scholastic reflection on the natural law follows the pattern of a tradition-based form of moral reasoning, and even though the scholastics did not understand their moral reflections specifically in those terms, their concept of the natural law is congruent with a modern understanding of it as a tradition of inquiry.